Difference between revisions of "Bicycle"

From WOI Encyclopedia Italia
Jump to navigation Jump to search
 
m
 
(11 intermediate revisions by 2 users not shown)
Line 1: Line 1:
−
{{otheruses}}
+
{{X}}
−
[[Image:Kusuma bike large.jpg|thumb|300px|This ''[[Racing bicycle|racing bicycle]]'' is built using lightweight, shaped aluminium tubing and [[Graphite-reinforced plastic|carbon fiber]] stays and forks.  It sports a drop handlebar and thin tires and wheels for efficiency and aerodynamics]]
+
[[Image:Kusuma bike large.jpg|thumb|300px|This ''[[racing bicycle]]'' is built using lightweight, shaped [[aluminium]] tubing and [[Graphite-reinforced plastic|carbon fiber]] stays and forks.  It sports a drop handlebar and thin tires and wheels for efficiency and aerodynamics.]]
 +
[[Image:Mountain bicycle.jpg|thumb|300px|This ''[[Mountain bike|mountain bicycle]]'' features oversized tires, a sturdy frame, front shock absorbers, and handlebars oriented perpendicular to the bike's axis]]
  
−
[[Image:utility bicycle.jpg|thumb|300px|Dutch utility bicycle featuring rear internal hub brake, chaincase and mudguards, kickstand for parking, permanently attached dynamo-powered lamps and touring handlebars.]]
 
  
−
A '''bicycle''', or '''bike''', is a pedal-driven [[land vehicle]] with two [[wheel]]s attached to a frame, one behind the other. First introduced in [[19th century|19th-century]] [[Europe]], bicycles evolved quickly into their familiar, current design. Numbering over 1,000,000,000 in the world today, bicycles provide the principal means of transportation in many regions and a popular form of recreation and transport in others.
+
A '''bicycle''', or '''bike''', is a [[bicycle pedal|pedal-driven]] [[human-powered transport|human-powered vehicle]] with two [[bicycle wheel|wheels]] attached to a [[bicycle frame|frame]], one behind the other. First introduced in [[19th century|19th-century Europe]], bicycles evolved quickly into their familiar, current design. Numbering over a billion worldwide. Bicycles provide the principal means of transportation in many regions, are a popular form of [[recreation]], and have been adapted for use in many other fields of human activity, including children's [[toy]]s, adult [[fitness]], [[military]] and local [[police]] applications, [[courier]] services, and cycle [[sports]].
  
−
The bicycle has affected history considerably in both the cultural and industrial realms. In its early years, bicycle construction drew on pre-existing technologies; more recently, bicycle technology has contributed, in turn, to other, newer areas. Beyond recreation and transportation, bicycles have been adapted for use in many occupations, including the military, local policing, courier services, and sports.  A recurrent theme in bicycling has been the tension between bicyclists and drivers of [[motor vehicle]]s, each group of whom argues for its fair share of the world's roadways.  According to members of [[Critical Mass]], a bicycle activist group, "We aren't blocking traffic, we ''are'' traffic!"
+
The basic shape and configuration of the bicycle's frame, wheels, pedals, saddle, and handlebars have hardly changed since the first chain-driven model was developed around 1885, although many important details have since been improved, especially since the advent of modern materials and computer-aided design. These have allowed for a proliferation of specialized designs for individuals who pursue a particular type of [[cycling]].
 +
 
 +
The bicycle has affected history considerably, in both the cultural and industrial realms. In its early years, bicycle construction drew on pre-existing technologies; more recently, bicycle technology has, in turn, contributed ideas in both old and newer areas.
  
 
==History==
 
==History==
 +
''Main article'' [[History of the bicycle]]
  
−
''Main article: [[History of the bicycle]]''
+
Several inventors and innovators contributed to the development of the bicycle. Its earliest known forebears were called ''[[velocipede]]s'', and included many types of human-powered vehicles.  One of these, the scooter-like ''[[dandy horse]]'' of the French Comte de Sivrac, dating to 1790, was long cited as the earliest bicycle. Most bicycle historians now believe that these hobby-horses with no steering mechanism probably never existed, but were made up by [[Louis Baudry de Saunier]], a 19th-century French bicycle historian.
 +
[[Image:bicycle two 1886.jpg|thumb|280px|A smartly dressed couple seated on an 1886 "[[quadricycle]]" for two]]
 +
The ancestor of the bicycle was probably first created by a German Baron, [[Karl Drais|Karl Drais]], who invented and patented his machine in 1817.  A number of these ''draisines'' still exist, including one at the ''Paleis het Loo'' museum in [[Apeldoorn]], the Netherlands. These were ''pushbikes'', powered by the action of the rider's feet pushing against the ground.  Scottish blacksmith [[Kirkpatrick MacMillan]] refined this in 1839 by adding a mechanical crank drive to the rear wheel, thus creating the first true "bicycle" in the modern sense. His system employed a pair of treadle drives connected by rods to a rear wheel crank, rather like a steam locomotive's driveshaft. Although the design was copied by at least two other Scottish builders, it was overtaken in popularity and influence by an inferior one. In the 1850s and 1860s, Frenchmen Ernest [[Michaux]] and [[Pierre Lallement]] took bicycle design in a different direction, placing the pedals on an enlarged front wheel. Their creation, which came to be called the "Boneshaker", featured a heavy steel frame on which they mounted wooden wheels with iron tires. Lallement emigrated to America, where he recorded a patent on his bicycle in 1866 in [[New Haven, Connecticut]]. The Boneshaker was further refined by James Starley in the 1870s. He mounted the seat more squarely over the pedals so that the rider could push more firmly, and further enlarged the front wheel to increase the potential for speed. With tires of solid rubber, his machine became known as ''the ordinary''. British cyclists likened the disparity in size of the two wheels to their coinage, nicknaming it the ''[[penny-farthing]]''. The primitive bicycles of this generation were difficult to ride, and the high seat and poor weight distribution made for dangerous falls.
 +
''[[Image:BicyclePlymouth.jpg|left|thumb|Bicycle in Victorian Plymouth, with a predecessor of the Starley diamond-frame]]''  
  
−
No single time or person can be identified with the invention of the bicycle. Its earliest known forebears were called ''[[velocipede]]s'', and included many types of human-powered vehicles.  One of these, the scooter-like ''[[dandy horse]]'', of the French Comte de Sivrac, dating to [[1790]], was long cited as the earliest bicycle. Most bicycle historians now believe that these hobby-horses with no steering mechanism probably never existed, but were instead made up by [[Louis Baudry de Saunier]], a 19th-century French bicycle historian.
+
The subsequent ''dwarf ordinary'' addressed some of these faults by adding gearing, reducing the front wheel diameter, and setting the seat further back, with no loss of speed. Having to both pedal and steer via the front wheel remained a problem. Starley's nephew, [[J. K. Starley]], J. H. Lawson, and Shergold solved this problem by introducing the ''chain'' and producing rear-wheel drive. These models were known as ''dwarf safeties'', or ''safety bicycles'', for their lower seat height and better weight distribution. Starley's 1885 Rover is usually described as the first recognizably modern bicycle. Soon, the ''seat tube'' was added, creating the double-triangle, ''diamond frame'' of the modern bike.
−
[[Image:bicycle two 1886.jpg|thumb|280px|A smartly dressed couple seated on an 1886 "bicycle" for two.]]
 
−
The most likely originator of the bicycle is German [[Karl Drais|Baron Karl von Drais]], who rode his [[1816]] machine while collecting taxes from his tenants. He patented his ''draisine'', a number of which still exist, including one at the ''Paleis het Loo'' museum in [[Apeldoorn]], [[the Netherlands]]. These were ''pushbikes'', powered by the action of the rider's feet pushing against the ground. Scottish blacksmith [[Kirkpatrick MacMillan]] shares creative credit with von Drais for adding a ''treadle'' drive mechanism, in [[1840]], that enabled the rider to lift his feet off the ground while driving the rear wheel. However, some reports describe MacMillan's vehicle as more of a "quadricycle".
 
  
−
In the [[1850s]] and [[1860s]], Frenchman Ernest Michaux and his pupil Pierre Lallement took bicycle design in a different direction, placing pedals on an enlarged front wheel.  Their creation, which came to be called the "Boneshaker", featured a heavy steel frame on which they mounted wooden wheels with iron tires. Lallement emigrated to America, where he recorded a patent on his bicycle in 1866. The Boneshaker was further refined by James Starley in the [[1870s]].  He mounted the seat more squarely over the pedals, so that the rider could push more firmly, and further enlarged the front wheel to increase the potential for speed. With tires of solid rubber, his machine became known as the ''ordinary''. British cyclists likened the disparity in size of the two wheels to their coinage, nicknaming it the ''[[penny-farthing]]''. The primitive bicycles of this generation were difficult to ride, and the high seat and poor weight distribution made for dangerous falls.
+
While the Starley design was much safer, the return to smaller wheels made for a bumpy ride. The next innovations increased comfort and ushered in the 1890s ''Golden Age of Bicycles''. In 1888, Scotsman [[John Boyd Dunlop]] introduced the [[pneumatic tire]], which soon became universal. Soon after, the rear [[freewheel]] was developed, enabling the rider to coast without the pedals spinning out of control. This refinement led to the 1898 invention of ''coaster brakes''. [[Derailleur gears]] and hand-operated, [[Bicycle brake systems|cable-pull brakes]] were also developed during these years, but were only slowly adopted by casual riders. By the turn of the century, bicycling clubs flourished on both sides of the Atlantic, and touring and racing were soon extremely popular.
−
+
[[Image:Bamboobike.jpg|thumb|American bike from 1896. The frame is made of [[bamboo]]]]
−
The subsequent ''dwarf ordinary'' addressed some of these faults, by adding some kind of gearing, reducing the front wheel diameter and setting the seat further back with no loss of speed. However, having to both pedal and steer via the front wheel remained a problem. Starley's nephew, [[J. K. Starley]], J. H. Lawson, and Shergold solved this problem by introducing the ''chain'' and producing rear-wheel drive.  These models were known as ''dwarf safeties'', or ''safety bicycles'', for their lower seat height and better weight distribution.  Starley's [[1885]] Rover is usually described as the first recognizably modern bicycle.  Soon the ''seat tube'' was added, creating the double-triangle, ''diamond frame'' of the modern bike.
+
[[Image:Amsterdam-flowerbike.jpg|thumb|A more-than-typical Amsterdam 'granny bike']]Successful early bicycle manufacturers included Englishman [[Frank Bowden]] and German builder Ignaz Schwinn. Bowden started the [[Raleigh (bicycle)|Raleigh]] company in Nottingham in the 1890s, and was soon producing some 30,000 bicycles a year. Schwinn emigrated to the United States, where he founded his similarly successful company in Chicago in 1895. [[Schwinn Bicycle Company|Schwinn]] bicycles soon featured widened tires and spring-cushioned, padded seats, sacrificing a certain amount of efficiency for increased comfort. Facilitated by connections between European nations and their overseas colonies, European-style bicycles were soon available worldwide. By the mid-20th century, bicycles had become the primary means of transportation for millions of people around the globe.
−
''[[Image:BicyclePlymouth.jpg|left|thumb|Bicycle in Victorian Plymouth, with a predecessor of the Starley diamond-frame]]''
 
−
 
−
While the Starley design was much safer, the return to smaller wheels made for a bumpy ride. The next innovations increased comfort and ushered in the [[1890s]] ''Golden Age of Bicycles''. In [[1888]] Scotsman [[John Boyd Dunlop]] introduced the [[pneumatic tire]], which soon became universal. Shortly thereafter the rear [[freewheel]] was developed, enabling the rider to coast without the pedals spinning out of control. This refinement led to the [[1898]] invention of ''coaster brakes''. [[Derailleur gears]] and hand-operated, [[Bicycle brake systems|cable-pull brakes]] were also developed during these years, but were only slowly adopted by casual riders. By the turn of the century, bicycling clubs flourished on both sides of the Atlantic, and touring and racing were soon the rage.
 
  
−
Successful early bicycle manufacturers included Englishman [[Frank Bowden]] and German builder Ignaz Schwinn. Bowden started the [[Raleigh (bicycle)|Raleigh]] company in Nottingham in the 1890s, and soon was producing some 30,000 bicycles a year. Schwinn emigrated to the United States, where he founded his similarly successful company in Chicago in [[1895]]. [[Schwinn Bicycle Company|Schwinn]] bicycles soon featured widened tires and spring-cushioned, padded seats, sacrificing some efficiency for increased comfort.  Facilitated by connections between European nations and their overseas colonies, European-style bicycles were soon available worldwide. By the mid-[[20th century]] bicycles had become the primary means of transportation for millions of people around the globe.
+
In many western countries, the use of bicycles levelled off or declined as motorized transportation became affordable and car-centred policies led to an increasingly hostile environment for bicycles. In North America, bicycle sales declined markedly after 1905, to the point where, by the 1940s, they had largely been relegated to the role of children's toys. However, in other parts of the world, such as China, India, and European countries such as Germany, Denmark, and the Netherlands, the traditional utility bicycle remained a mainstay of transportation; its design changed only gradually to incorporate hand-operated brakes, with internal hub gears allowing up to seven speeds. In the Netherlands, such so-called 'granny bikes' have remained popular, and are again in production.  
  
−
[[image:Amsterdam-flowerbike.jpg|thumb|300px|A more-than-typical Amsterdam 'granny bike']]
+
In North America, increasing consciousness of physical fitness and environmental preservation spawned a renaissance of bicycling in the late 1960s. Bicycle sales in the US boomed, largely in the form of the [[racing bicycle]]s, long used in such events as the hugely popular [[Tour de France]]. Sales were also helped by a number of technical innovations that were new to the US market, including higher performance steel alloys and gearsets with an increasing number of gears. While 10-speeds were the rage in the 1970s, 12-speed designs were introduced in the 1980s, and today most bikes feature 18 or more speeds. By the 1980s, these newer designs had driven the [[three-speed bicycle]] from the roads. In the late 1980s, the [[mountain bike]] became particularly popular, and in the 1990s something of a major fad. These task-specific designs led many American recreational cyclists to demand a more comfortable and practical product.  Manufacturers responded with the [[hybrid bicycle]], which restored many of the features long enjoyed by riders of the time-tested European [[utility bicycle|utility bikes]].
−
In many western countries the use of bicycles levelled off or declined, as motorized transportation became affordable and car-centered policies led to an increasingly hostile road environment for bicycles. In North America, bicycle sales declined markedly after [[1905]], to the point where by the [[1940]]s, they had largely been relegated to the role of children's toys.  In other parts of the world however, such as [[China]], [[India]], and European countries such as [[Germany]], [[Denmark]], and the [[Netherlands]], the traditional utility bicycle remained a mainstay of transportation, its design only gradually changing to incorporate hand-operated brakes and internal hub gears allowing up to seven speeds. In the Netherlands, old style bicycles so-called 'granny bikes', have remained very popular and are again being produced now the original supply is turning to rust. Especially [[Amsterdam]] granny bikes are often colourfully painted and/or otherwise decorated.
 
−
 
 
−
[[Image:Mountain bicycle.jpg|thumb|left|This ''[[Mountain bike|mountain bicycle]]'' features oversized tires, a sturdy frame, front shock absorbers, and handlebars oriented perpendicular to the bike's axis]]
 
−
In North America, increasing consciousness of physical fitness and environmental preservation spawned a renaissance of bicycling in the late [[1960s]]. Bicycle sales in the United States boomed, largely in the form of the [[racing bicycle]]s long used in such events as the hugely popular [[Tour de France]]. Sales were also helped by a number of technical innovations that were new to the US market, including higher performance steel alloys and gearsets with an increasing number of gears. While 10-speeds were the rage in the 1970s, 12-speed designs were introduced in the 1980s, and today most bikes feature 18 or more speeds. By the 1980s these newer designs had driven the [[three-speed bicycle]] from the roads. In the late 1980s the [[mountain bike]] became particularly popular, and in the 1990s something of a major fad. These task-specific designs led many American recreational cyclists to demand a more comfortable and practical product.  Manufacturers responded with the [[hybrid bicycle]], which restored many of the features long enjoyed by riders of the time-tested European [[utility bicycle|utility bikes]].
 
  
 
==Technical aspects==
 
==Technical aspects==
 
[[Image:Bicycle.jpg|frame|Reflectors for night riding are one of many available safety accessories]]
 
[[Image:Bicycle.jpg|frame|Reflectors for night riding are one of many available safety accessories]]
  
−
=== Legal requirements ===
+
===Legal requirements===
−
The  1968 [[Vienna Convention on Road Traffic]] considers a bicycle to be a vehicle, and a person controlling a bicycle is considered a driver.  The traffic codes of many countries reflect these definitions and demand that a bicycle satisfy certain legal requirements, including licencing, before it can be used on public roads.  In many jurisdictions it is an offence to use a bicycle that is not in roadworthy condition and which does not have functioning front and rear [[bicycle brake systems|brakes]].  In some places, bicycles must have functioning front and rear [[bicycle lighting|lights]] or ''lamps''.  As some generator or dynamo-driven lamps only operate while moving, rear [[retroreflectors|reflectors]] are frequently also mandatory.  Since a moving bicycle makes very little noise, in many countries bicycles must have a warning bell for use when approaching pedestrians, equestrians and other bicyclists.
+
The  1968 [[Vienna Convention on Road Traffic]] considers a bicycle to be a vehicle, and a person controlling a bicycle is considered a driver.  The traffic codes of many countries reflect these definitions and demand that a bicycle satisfy certain legal requirements, sometimes even including licencing, before it can be used on public roads.  In many jurisdictions it is an offense to use a bicycle that is not in roadworthy condition.  In some places, bicycles must have functioning front and rear [[bicycle lighting|lights]] or ''lamps''.  As some generator or dynamo-driven lamps only operate while moving, rear [[retroreflectors|reflectors]] are frequently also mandatory.  Since a moving bicycle makes very little noise, in many countries bicycles must have a warning bell for use when approaching pedestrians, equestrians and other bicyclists.
  
 
===Construction and parts===
 
===Construction and parts===
−
 
 
====Frame====
 
====Frame====
 +
{{main|Bicycle frame}}
  
−
:''Main article: [[Bicycle frame]]''
+
Nearly all modern [[upright bicycle]]s feature the ''diamond frame'', composed of two [[triangle]]s: the front triangle and the rear triangle. The front triangle consists of the head tube, top tube, down tube and seat tube. The head tube contains the [[headset (bicycle part)|headset]], the set of bearings that allows the [[bicycle fork|fork]] to spin smoothly. The top tube connects the head tube to the seat tube at the top, and the down tube connects the head tube to the [[bottom bracket]]. The rear triangle consists of the seat tube and paired chain stays and seat stays. The chain stays run parallel to the [[bicycle chain|chain]], connecting the bottom bracket to the rear dropouts. The seat stays connect the top of the seat tube at or near the same point as the top tube) to the rear dropouts.
  
−
Nearly all modern [[upright bicycle]]s feature the ''diamond frame'', composed of two [[triangle]]s: the front triangle and the rear triangle. The front triangle consists of the head tube, top tube, down tube and seat tube. The head tube contains the [[headset (bicycle part)|headset]], the interface with the [[bicycle fork|fork]]. The top tube connects the head tube to the seat tube at the top, and the down tube connects the head tube to the [[bottom bracket]]. The rear triangle consists of the seat tube and paired chain stays and seat stays. The chain stays run parallel to the [[bicycle chain|chain]], connecting the bottom bracket to the rear dropouts. The seat stays connect the top of the seat tube (often at or near the same point as the top tube) to the rear dropouts.
+
Historically, women's bicycle frames had a top tube that connected in the middle of the seat tube instead of the top, resulting in a lower standover height. This allowed the rider to dismount while wearing a skirt or dress. Although some women's bicycles continue to use this frame style, there is also a hybrid form, the ''mixte'' or ''[[step-through frame]]'', which also allows easier mounting and dismounting for both male and female riders.
  
−
Historically, women's bicycle frames had a top tube that connected in the middle of the seat tube instead of the top, resulting in a lower standover height. This allowed the rider to dismount while wearing a skirt or dress. Although some women's bicycles continue to use this frame style, there is also a hybrid form, the ''mixte'' or ''step-through frame'', which also allows easier mounting and dismounting for both male and female riders.
+
Historically, materials used in bicycles have followed a similar pattern as in aircraft, the goal being strength and low weight.  Since the late 1930s alloy steels have been used for frame and fork tubes in higher quality machines. [[Celluloid]] found application in mudguards, and aluminium alloys are increasingly used in components such as handlebars, seat post, and brake levers. In the 1980s [[aluminium]] alloy frames became popular, and their affordability now makes them common.  More expensive [[carbon fiber]] and [[titanium]] frames are now also available, as well as advanced steel alloys.
−
 
 
−
Historically, materials used in bicycles have followed a similar pattern as in aircraft, the goal being strength and low weight.  Since the late 1930s alloy steels have been used for frame and fork tubes in higher quality machines. [[Celluloid]] found application in mudguards, and aluminum alloys are increasingly used in components such as handlebars, seat stems (also known as seatposts), and brake levers. In the [[1980s]] [[aluminum]] alloy frames became popular, and their affordability now makes them common.  More expensive [[carbon fibre]] and [[titanium]] frames are now also available, as well as advanced steel alloys.
 
  
 
====Drivetrain====
 
====Drivetrain====
 +
{{details|bicycle gearing}}
  
−
The ''drivetrain'' begins with [[bicycle pedal|pedals]] which rotate the [[crankset]], which fit into the [[bottom bracket]]. Attached to the crank is the ''chainring'' which drives the [[bicycle chain|chain]], which in turn rotates the rear wheel via the rear [[sprocket]]s. Between the chain and rear wheel may be interspersed various gearing systems, described below, which vary the [[gear ratio]], the number of rear wheel revolutions produced by each turn of the pedals.   
+
The ''drivetrain'' begins with [[bicycle pedal|pedals]] which rotate the [[crankset]], which fit into the [[bottom bracket]]. Attached to the crank is the ''chainring'' or sprocket which drives the [[bicycle chain|chain]], which in turn rotates the rear wheel via the rear [[sprocket]]s, or cassette. Various [[bicycle gearing|gearing systems]], described below, may be interspersed between the pedals and rear wheel; these gearing systems vary the number of rear wheel revolutions produced by each turn of the pedals.   
  
−
Since cyclists' legs produce a limited amount of power most efficiently over a narrow range of ''[[Cadence (cycling)|cadences]]'', a variable gear ratio is needed to maintain an optimum pedaling speed while covering varied terrain.  The gear systems are hand-operated, via cables (or rarely, hydraulics), and are of two types.
+
Since cyclists' legs produce a limited amount of power most efficiently over a narrow range of ''[[Cadence (cycling)|cadences]]'', a variable [[gear ratio]] is needed to maintain an optimum pedaling speed while covering varied terrain.  The gear systems are usually hand-operated, via cables (or rarely, hydraulics), and are of two types.
−
* ''Internal [[hub gear]]ing'' works by [[Epicyclic gearing|planetary, or epicyclic, gearing]], in which the outer case of the hub gear unit turns at a different speed relative to the rear axle depending on which gear is selected.  Rear hub gears may offer 3, 4, 5, 6, 7, 8, 12, or 14 speeds.  Bottom bracket fittings offer a choice of 2 speeds.   
+
* ''Internal [[hub gear]]ing'' works by [[Epicyclic gearing|planetary, or epicyclic, gearing]], in which the outer case of the hub gear unit turns at a different speed relative to the rear axle depending on which gear is selected.  Rear hub gears may offer 3, 4, 5, 6, 7, 8, 12, or 14 speeds.  Bottom bracket fittings offer a choice of 2 speeds, and are generally foot-operated.   
 
*  ''External gearing'' utilizes [[derailleur gear|derailleurs]], which can be placed on both the front ''chainring'' and on the rear ''cluster'' or ''cassette'', to push the chain to either side, derailing it from the sprockets. The sides of the gear rings catch the chain, pulling it up onto their teeth to change gears.  There may be 1 to 3 chainrings, and 5 to 10 sprockets on the cassette.
 
*  ''External gearing'' utilizes [[derailleur gear|derailleurs]], which can be placed on both the front ''chainring'' and on the rear ''cluster'' or ''cassette'', to push the chain to either side, derailing it from the sprockets. The sides of the gear rings catch the chain, pulling it up onto their teeth to change gears.  There may be 1 to 3 chainrings, and 5 to 10 sprockets on the cassette.
  
Line 62: Line 58:
 
Road bicycles have ''close set'' multi-step gearing, which allows very fine control of cadence, while ''utility cycles'' offer fewer, more widely spaced speeds. ''Mountain bikes'' and most entry-level road racing bikes may offer an extremely low gear to facilitate climbing slowly on steep hills.
 
Road bicycles have ''close set'' multi-step gearing, which allows very fine control of cadence, while ''utility cycles'' offer fewer, more widely spaced speeds. ''Mountain bikes'' and most entry-level road racing bikes may offer an extremely low gear to facilitate climbing slowly on steep hills.
  
−
Fixed-gear track racing bikes have transmission efficiencies of over 99% (nearly all the energy put in at the pedals ends up at the wheel). Whilst variable ratio gear mechanisms are essential for human efficiency, they do reduce mechanical efficiency. The efficiency varies considerably with the gear ratio being used. In a typical hub gear mechanism the mechanical efficiency will be between 82% and 92% depending on the ratio selected. Which ratios are ''best'' and ''worst'' depends on the specific model of hub gear. Derailleur type mechanisms fare better, with a typical mid-range product (of the sort used by serious amateurs) achieving between 88% and 99% efficiency at 100W. In derailleur mechanisms the highest efficiency is achieved by the larger cogs and, generally speaking, efficiency decreases with smaller cog sizes. This is because the chain must bend more sharply as it rolls on and off the cog, and also forms a sharp angle at the chain tensioner<sup>[[#Notes|9]]</sup>. Efficiency is also compromised on derailleur drivetrains if the chain is running large-ring to large-cog or small-ring to small-cog; this is called '''cross-chaining''', and also results in increased wear because of the lateral deflection of the chain. [[Retro-Direct]] was a type of drivetrain used on some bicycles in the early [[20th century]] that has been resurrected by bicycle hobbyists.
+
Fixed-gear track racing bikes have transmission efficiencies of over 99% (nearly all the energy put in at the pedals ends up at the wheel). While generally variable ratio gear mechanisms are essential for human efficiency, they do reduce mechanical efficiency. The efficiency varies considerably with the gear ratio being used. In a typical hub gear mechanism the mechanical efficiency will be between 82% and 92% depending on the ratio selected. Which ratios are ''best'' and ''worst'' depends on the specific model of hub gear. Derailleur type mechanisms fare better, with a typical mid-range product (of the sort used by serious amateurs) achieving between 88% and 99% efficiency at 100W. In derailleur mechanisms the highest efficiency is achieved by the larger cogs. Efficiency generally decreases with smaller cog sizes because the chain must bend more sharply as it rolls on and off the cog, and it also forms a sharp angle at the chain tensioner. See Chapter 9 of "Bicycling Science" (Reference, below) for details of transmission efficiency.</ref> Derailleur efficiency is also compromised with ''cross-chaining'', or running large-ring to large-cog or small-ring to small-cog. This also results in increased wear because of the lateral deflection of the chain. [[Retro-Direct]] drivetrains used on some early 20th century bicycles have been resurrected by bicycle hobbyists.
 +
 
 +
Some early 20th C. bicycles dispensed with the chain entirely and used an enclosed driveshaft and bevel gears. These were strongly built but were not mechanically efficient. They were primarily marketed to women as the enclosed gears would not entangle clothing.
  
 
====Steering and seating====
 
====Steering and seating====
 +
The [[handlebar]]s rotate the [[bicycle fork|fork]] and the front [[bicycle wheel|wheel]] via the ''stem'', which articulates with the [[headset (bicycle part)|headset]].  Three styles of handlebar are common.  ''Touring handlebars'', the norm in Europe and elsewhere until the 1970s, curve gently back toward the rider, offering a natural grip and comfortable upright position.  ''Racing handlebars'' are "dropped", offering the cyclist either an aerodynamic "hunched" position or a more upright posture in which the hands grip the brake lever mounts.  Mountain bikes feature a crosswise handlebar, which helps prevent the rider from pitching over the front in case of sudden deceleration.
  
−
The [[handlebar]]s rotate the [[bicycle fork|fork]] and the front [[bicycle wheel|wheel]] via the ''stem'', which articulates with the [[headset (bicycle part)|headset]]. Three styles of handlebar are common.  ''Touring handlebars'', the norm in Europe and elsewhere until the [[1970s]], curve gently back toward the rider, offering a natural grip and comfortable upright position. ''Racing handlebars'' are "dropped", offering the cyclist either an aerodynamic "hunched" position or a more upright posture in which the hands grip the brake lever mounts.  Mountain bikes feature a crosswise handlebar, which helps prevent the rider from pitching over the front in case of sudden deceleration.
+
Variations on these styles exist. ''Bullhorn'' style handlebars are often seen on modern [[time trial bicycle]]s, equipped with two forward-facing extensions, allowing a rider to rest his entire forearm on the bar. These are usually used in conjunction with the ''aero bar'', a pair of forward-facing extensions spaced close together, to promote better aerodynamics. The ''Bullhhorn'' was banned from ordinary road racing because it is difficult for the rider to control in bike traffic.
  
−
Variations on these styles exist. The ''Bullhorn'' style handlebars are often seen on modern Time Trial specific bicycles, equipped with two forward-facing extensions, allowing a rider to rest his entire forearm on the bar. These are usually used in conjunction with the ''aero bar'', a pair of forward-facing extensions spaced close together, to allow the rider a position of increased aerodynamics. The ''Bullhorn'' style handlebars are banned from ordinary road racing because it is considered there is less fine control in bike traffic.
+
''Seats'', or ''saddles'', also vary with rider preference, from the cushioned ones favoured by short-distance riders to narrower seats which allow more free leg swings. Comfort depends on riding position.  With comfort bikes and hybrids the cyclist sits high over the seat, their weight directed down onto the saddle, such that a wider and more cushioned saddle is preferable. For racing bikes where the rider is bent over, weight is more evenly distributed between the handlebars and saddle, and the hips are flexed, and a narrower and harder saddle is more efficient.  
−
 
−
''Seats'', or ''saddles'', also vary depending on rider preference, from the cushioned ones favoured by short-distance riders to narrower seats which allow more free leg swings. Comfort depends on riding position.  With comfort bikes and hybrids the cyclist sits high over the seat, their weight directed down onto the saddle, such that a wider and more cushioned saddle is preferable. For racing bikes where the rider is bent over, weight is more evenly distributed between the handlebars and saddle, and the hips are flexed. For this style of riding a narrower and harder saddle is more efficient.  
 
  
 
[[Recumbent bicycle]]s have more chair-like seats, and so are much more comfortable to ride, although generally slower up hills due to this positioning.  The reclined, low seating position does provide increased aerodynamics over standard seating.
 
[[Recumbent bicycle]]s have more chair-like seats, and so are much more comfortable to ride, although generally slower up hills due to this positioning.  The reclined, low seating position does provide increased aerodynamics over standard seating.
  
 
====Brakes====
 
====Brakes====
 +
{{main|bicycle brake systems}}
  
−
:''Main article: [[Bicycle brake systems]]''
+
Modern bicycle ''brakes'' are either ''rim brakes'', in which friction pads are compressed against the wheel rims, ''internal hub brakes'', in which the friction pads are contained within the wheel hubs, or disc brakes.  A rear hub brake may be either hand-operated or pedal-actuated, as in the back pedal ''coaster brakes'' which were the rule in North America until the 1960s.  Hub drum brakes do not cope well with extended braking, so rim brakes are favoured in hilly terrain.  With hand-operated brakes, force is applied to brake handles mounted on the handle bars and then transmitted via [[Bowden cable]]s to the friction pads.  In the late 1990s, [[disc brakes]] appeared on some off-road bicycles, [[tandem bicycle|tandem]]s and [[recumbent bicycle]]s, but are considered impractical on road bicycles, which rarely encounter conditions where the advantages of discs are significant. 
  
−
Bicycle ''brakes'' are either ''rim brakes'', in which friction pads are compressed against the wheel rims, ''internal hub brakes'', in which the friction pads are contained within the wheel hubs, or disc brakes.  A rear hub brake may be either hand-operated or pedal-actuated, as in the back pedal ''coaster brakes'' which were the rule in North America until the [[1960]]s.  Hub drum brakes do not cope well with extended braking, so rim brakes are favoured in hilly terrain.  With hand-operated brakes, force is applied to brake handles mounted on the handle bars and then transmitted via [[Bowden cable]]s to the friction pads.  In the late [[1990s]], [[disc brakes]] appeared on some off-road bicycles, [[tandem bicycle|tandem]]s and [[recumbent bicycle]]s, but are considered impractical on road bicycles, which rarely encounter conditions where the advantages of discs are significant.
+
The advantages of discs make them well-suited to steep, extended downhills through wet and muddy off-road terrain, which falls under the category of downhill and freeride bicycle riding.  The use of tires as large as 3.0 inches in width also makes disc brakes a necessity, as rim brakes simply cannot straddle a tire that wide.
  
−
The advantages of discs make them well-suited to steep, extended downhills through wet and muddy off-road terrain, which falls under the category of downhill and freeride bicycle riding.  The use of tires as large as 3.0 inches in width also makes disc brakes a necessity, as rim brakes simply cannot straddle a tire that wide.
+
Two main disc brake systems exist: hydraulic and mechanical (cable-actuated).  Mechanical disc brakes have less modulation than hydraulic disc brake systems, and since the cable is usually open to the outside, mechanical disc brakes tend to pick up small bits of dirt and grit in the cable lines when ridden in harsh terrain.  Hydraulic disc brake systems generally keep contaminants out better.  However, since hydraulic disc brakes usually require relatively specialized tools to bleed the brake systems, repairs on the trail are difficult to perform, whereas mechanical disc brakes rarely fail.  Also, the hydraulic fluid may boil on steep, continuous downhills.  This is due to heat building up in the disc and pads and can cause the brake to lose its ability to transmit force through incompressible fluids, since some of it has become a gas, which is compressible.  To avoid this problem, 203 mm (8 inch) diameter disc rotors have become common on downhill bikes.  Larger rotors dissipate heat more quickly and have a larger amount of mass to absorb heat.  For these reasons, one must weigh the advantages and disadvantages of using a hydraulic system versus a mechanical system.
  
−
Two main disc brake systems exist: hydraulic and mechanical (cable-actuated).  Mechanical disc brakes have less modulation than hydraulic disc brake systems, and since the cable is usually open to the outside, mechanical disc brakes tend to pick up small bits of dirt and grit in the cable lines when ridden in harsh terrain.  Hydraulic disc brake systems generally keep contaminants out better.  However, since hydraulic disc brakes usually require relatively specialized tools to bleed the brake systems, repairs on the trail are difficult to perform, whereas mechanical disc brakes rarely fail.  Also, the hydraulic fluid may boil on steep, continuous downhills.  This is due to the brake losing its ability to transmit force through incompressible fluids, since some of it has become a gas, which is compressible.  For these reasons, one must weigh the advantages and disadvantages of using a hydraulic system versus a mechanical system.
+
For [[track cycling]], [[track bicycle]]s do not have brakes.  Most track bike frames and forks do not have holes for mounting brakes, although with their increasing popularity among some road cyclists, some  manufacturers have drilled their track frames to enable the fitting of brakes.  Brakes are not required for riding on a track because all riders ride in the same direction and there are no corners or other traffic. Track rider are still able to slow down because all track bicycles are [[fixed gear|fixed]], meaning that there is no freewheel.  Without a freewheel, coasting is impossible, so when the rear wheel is moving, the crank is moving.  To slow down one may apply resistance to the pedals.  Cyclists who ride a track bike without brake(s) on the road can also slow down by skidding, by unweighting the rear wheel and applying  a backwards force to the pedals, causing the rear wheel to lock up and slide along the road.
  
 
====Accessories and repairs====
 
====Accessories and repairs====
−
 
 
Utility bicycles have many standard features which enhance their usefulness and comfort that would be considered accessories on sports bicycles.  ''Chainguards'' and ''mudguards'', or ''fenders'', protect clothes and moving parts from oil and spray.  ''Kick stands'' help with parking.  Front-mounted wicker or steel ''baskets'' for carrying goods are often used.  Rear racks or carriers can be used to carry items such as school satchels.  Parents sometimes add rear-mounted child seats and/or an auxiliary saddle fitted to the crossbar to transport children.
 
Utility bicycles have many standard features which enhance their usefulness and comfort that would be considered accessories on sports bicycles.  ''Chainguards'' and ''mudguards'', or ''fenders'', protect clothes and moving parts from oil and spray.  ''Kick stands'' help with parking.  Front-mounted wicker or steel ''baskets'' for carrying goods are often used.  Rear racks or carriers can be used to carry items such as school satchels.  Parents sometimes add rear-mounted child seats and/or an auxiliary saddle fitted to the crossbar to transport children.
−
[[Image:Reiserad-beladen.jpg|left|thumb|Touring bicycle equipped with head lamp, pump, rear rack, fenders/mud-guards, and numerous saddle-bags.]]
+
[[Image:Reiserad-beladen.jpg|right|thumb|Touring bicycle equipped with head lamp, pump, rear rack, fenders/mud-guards, and numerous saddle-bags.]]
−
Other accessories include lights, pump, lock, and additional (pedal or wheel-mounted) reflectors.  Technical accessories include solid-state speedometers and odometers for measuring distance.  ''Toe-clips'' help to keep the foot planted firmly on the pedals, and enable the cyclist to pull as well as push the pedals.
+
Other accessories include lights, pump, lock, and additional (pedal or wheel-mounted) reflectors.  Technical accessories include solid-state speedometers and odometers for measuring distance.  ''Toe-clips and toestraps'' help to keep the foot planted firmly on the pedals, and enable the cyclist to pull as well as push the pedals.
  
−
In North America, a large minority, possibly up to 25% in the US, of bicyclists wear plastic [[bicycle helmet]]s for safety. There is no US federal law requiring the use of helmets, but the majority of states require children up to a certain age to wear them; a number of cities and counties in [[Washington]] require them for riders of all ages. In most European countries, helmets are viewed as an indicator of inexperience or recklessness, and their use is considered unusual for adult utility cyclists.  In [[Australia]] and [[New Zealand]], and parts of [[Canada]], such helmets are required by law. The use of helmets by utility cyclists is practically unknown in most other regions.
+
In most countries where cycling is common, [[bicycle helmet]] use is negligible.  In North America a significant minority, possibly up to 25% of bicyclists, wear helmets. While no U.S. federal law requires helmets, many states require children to wear them, and some municipalities require them for all riders. In [[Australia]] and [[New Zealand]], and parts of [[Canada]], helmets are required by law. Outside the West, use of helmets by utility cyclists is practically unknown.  No correlation between decreased injury rates and helmet use has been demonstrated in whole populations.
  
−
Many cyclists also carry ''tool kits'', containing at least a patch kit for tires, [[tire lever]]s, and some spanners. At one time it was possible to use a single tool to carry out most common bicycle repairs.  More specialised parts now often require more complex tools, including proprietary tools specific for a given manufacturer.  Some bicycle parts, particularly hub-based gearing systems, are complex, and many people prefer to leave most [[repair and maintenance|maintenance and repairs]] to professionals.  Others maintain their own bicycles, finding it enhances their enjoyment of the [[hobby]] of cycling.
+
Many cyclists carry ''tool kits'', containing at least a tire patch kit (and/or a spare tube), [[tire lever]]s, and allen wrenches. A single tool once sufficed for most repairs.  More specialised parts now require more complex tools, including proprietary tools specific for a given manufacturer.  Some bicycle parts, particularly hub-based gearing systems, are complex, and many prefer to leave [[repair and maintenance|maintenance and repairs]] to professionals.  Others maintain their own bicycles, enhancing their enjoyment of the [[hobby]] of cycling.
  
 
===Performance===
 
===Performance===
 +
In both biological and mechanical terms, the bicycle is extraordinarily efficient. In terms of the amount of energy a person must expend to travel a given distance, investigators have calculated it to be the most efficient self-powered means of transportation.  From a mechanical viewpoint, up to 99% of the energy delivered by the rider into the pedals is transmitted to the wheels, although the use of gearing mechanisms may reduce this by 10-15%. In terms of the ratio of cargo weight a bicycle can carry to total weight, it is also a most efficient means of cargo transportation.
  
−
In both biological and mechanical terms, the bicycle is extraordinarily efficient. In terms of the amount of energy a person must expend to travel a given distance, investigators have calculated it to be the most efficient self-powered means of transportation.<sup>[[#Notes|1]]</sup>  From a mechanical viewpoint, up to 99% of the energy delivered by the rider into the pedals is transmitted to the wheels, although the use of gearing mechanisms may reduce this by 10-15% <sup>[[#Notes|2]]</sup>  <sup>[[#Notes|9]]</sup>. In terms of the ratio of cargo weight a bicycle can carry to total weight, it is also a most efficient means of cargo transportation.
+
A human being travelling on a bicycle at low to medium speeds of around 10-15 mph (16-24 km/h), using only the energy required to walk, is the most energy-efficient means of transport generally available. Air drag, which increases with the square of speed, requires increasingly higher power outputs relative to speed. A bicycle in which the rider lies in a prone position and which may be covered in an aerodynamic fairing to achieve very low air drag is referred to as a [[Recumbent bicycle]] or [[Human Powered Vehicle]].
  
−
[[Image:RacingBicycle-non.JPG|right|thumb|Racing bicycles have dropped handlebars, a narrow seat, and minimal accessories.]]
+
For more detail, see [[bicycle performance]]
  
−
On firm, flat, ground, a 70 kg man requires about 100 watts to walk at 5 km/h. That same man on a bicycle, on the same ground, with the same power output, can average 25 km/h, so energy expenditure in terms of kcal/kg/km is roughly one-fifth as much. Generally used figures are
+
===Balance===
−
* 1.62 kJ/(km∙kg) or 0.28 kcal/(mile∙lb) for cycling,
+
{{main|Bicycle and motorcycle dynamics}}
−
* 3.78 kJ/(km∙kg) or 0.653 kcal/(mile∙lb) for walking/running,
 
−
* 16.96 kJ/(km∙kg) or 2.93 kcal/(mile∙lb) for swimming.
 
  
−
For many people whose running might be limited by muscle and knee pain, cycling offers comparable outdoor exercise that can be enjoyed by people of a wide range of fitness levels: it is a "no-impact" sport that is easy on the body as long as the bike is properly "fit."  In addition, since bicycling can also provide convenient transportation, less self-discipline may be required to keep to the activity, since it has a  practical purpose. However, because of its efficiency, cycling requires a longer distance, and often greater time, than running to consume the same amount of energy.
+
A bicycle stays upright when it is steered to keep its center of gravity over its wheels. Lock the steering of a bicycle and it is virtually impossible to ride. Cancel the gyroscopic effect of rotating bicycle wheels by adding counter-rotating wheels, and it can still be easily ridden.
  
−
The average "in-shape" man can produce about 3 watts/kg for more than an hour (e.g., around 200 watts for a 70 kg rider), with top amateurs producing 5 watts/kg and elite athletes achieving 6 watts/kg for similar lengths of time. Elite track sprinters are able to attain an instantaneous maximum output of around 2,000 watts, or in excess of 25 watts/kg; elite road cyclists may produce 1,600 to 1,700 watts as an instantaneous maximum in their burst to the finish line at the end of a five-hour long road race. Even at moderate speeds, most cycling energy is spent in overcoming aerodynamic [[drag (physics)|drag]], which increases with the square of speed; therefore, power needs increase approximately with the cube of speed.
+
===Further reading===
−
 
−
Typical speeds for bicycles are 16 to 32&nbsp;[[km/h]] (10 to 20&nbsp;[[mph]]). On a fast racing bicycle, a reasonably fit rider can ride at 50&nbsp;km/h (30&nbsp;mph) on flat ground for short periods. The highest speed ever officially attained on the flat, without using motor pacing and wind-blocks, is by Canadian [[Sam Whittingham]], who in [[2002]] set a 130.36&nbsp;km/h (81.00&nbsp;mph) record on his highly aerodynamic [[recumbent bicycle]]. This stands as the official record for all human-powered vehicles.
 
−
 
 
−
There has been major corporate competition to lower the weight of racing bikes through the use of advanced materials and components. Additionally, advanced wheels are available with low-friction bearings and other features to lower road resistance. In measured tests these components have almost no effect on cycling performance. For instance, lowering a bike's weight by 1 kg, a major effort considering they may weigh less than 15 kg to start with, will have the same effect over a 40 km [[time trial]] as removing a protrusion into the air the size of a pencil. For this reason more recent designs have concentrated on lowering wind resistance, using aerodynamically shaped tubing, flat spokes on the wheels, and handlebars that allow the rider to bend over into the wind. These changes can impact performance dramatically, cutting minutes off a time trial.
 
−
 
 
−
===Bicycle physics===
 
−
A rider stays upright on a bicycle by steering the bicycle so that the point where the wheels touch the ground stays underneath the center of gravity. Once underway, this effort is largely replaced by physical forces generated by the rotation of the wheels which produce a remarkable "self-steering" effect.<sup>[[#Notes|3]]</sup> The [[angular momentum]] of the wheels and the [[torque]] applied to them by the ground generates a phenomenon called [[precession]], by which the wheel turns, or ''trails'', toward whichever side the bicycle tilts. Like the rider's steering adjustments, this motion automatically returns the contact point of the wheel directly under the center of gravity.  These forces, perhaps aided at very high speeds by the gyroscopic effect of the spinning wheels,<sup>[[#Notes|4]]</sup> are sufficiently strong that a riderless bicycle going down a slope will stay upright by itself.  Conversely, a bicycle whose steering fork is ''locked'' in a perfectly straight ahead position is virtually impossible to balance.
 
−
 
 
−
That gyroscopic effects are unimportant at normal cycling speeds was shown by physicist and researcher into bicycle stability [[David E. H. Jones]], whose series of "URBs" ("unrideable bikes" with various modifications to the front end) included a bike which cancelled the gyroscopic effect of the front wheel by dint of attaching a second wheel to his front forks (alongside the regular wheel) whose lower edge was about an inch (25 mm) above the ground.  By gearing this wheel to the regular front wheel so that it spun in the opposite direction at equal speed, the net angular momentum of both wheels together was close to zero.  Jones found he could ride this bike with no difficulty, but did discover that without a rider the non-gyroscopic bike fell over much faster than a regular bike.
 
−
 
 
−
Stability is also influenced by a geometric factor called ''trail''. This is the distance between the point of contact the front wheel makes with the ground and the place the steering axis makes contact with the ground. The greater the amount of trail, the greater the reaction. One can see the effect that trail has by simply holding a bicycle by the seat and leaning it. The moment due to trail and the weight of the bicycle will turn the front wheel in the direction of the turn. Negative trail (rolling a bicycle backwards) results in immediate steering problems. Zero trail (as in a unicycle) requires constant rider adjustment. Positive trail - found on typical bicycles - creates positive stability by steering the contact patch back under the CG of the bicycle and rider. [http://www.johnforester.com/Articles/BicycleEng/dahon.htm] [http://www.velonews.com/tech/report/articles/7322.0.html]
 
−
 
 
−
At higher speeds bicycles can also experience [[speed wobble|speed wobbles]] or shimmies, where the front wheel spontaneously oscillates to the left and right.  While the wobbles can be easily remedied by slowing down, adjusting position, or relaxing one's grip on the handlebars, speed wobbles can be [http://www.mailtribune.com/archive/2004/0915/local/stories/01local.htm fatal]
 
−
 
 
−
This shimmy is often seen in shopping cart front wheels. Some otherwise minor irregularity accelerates the wheel to one side. The restoring force is applied in phase with the progress of the irregularity, and the wheel turns to the other side where the process is repeated. If there is insufficient damping in the steering the oscillation will increase until system failure. Speed changes, making the bicycle/motorcycle stiffer or lighter, or increasing the stiffness of the steering (of which the rider is the main component) can change the oscillation frequency, though only speed change is applicable in the situation.
 
  
 
For more information on the technical aspects of bicycles, see also:
 
For more information on the technical aspects of bicycles, see also:
Line 129: Line 110:
 
<!-- *[[Bicycle brake systems]] -->
 
<!-- *[[Bicycle brake systems]] -->
 
<!-- *[[Bicycle lighting]] -->
 
<!-- *[[Bicycle lighting]] -->
 +
<!-- *[[Bicycle physics]] -->
  
 
==Social and historical aspects==
 
==Social and historical aspects==
 
[[Image:BikesInAmsterdam 2004 SeanMcClean.jpg|right|thumb|Present day: Bikes still popular in Amsterdam]]
 
[[Image:BikesInAmsterdam 2004 SeanMcClean.jpg|right|thumb|Present day: Bikes still popular in Amsterdam]]
  
−
===Economic and social implications===
+
===Economic implications===
 +
Bicycle manufacturing proved to be a training ground for other industries.  Building modern bicycle frames led to the development of advanced metalworking techniques, both for the frames themselves and for special components such as [[Bearing (mechanical)|ball bearings]], [[washer (mechanical)|washer]]s, and [[sprocket]]s. These techniques later enabled skilled metalworkers and mechanics to develop the components used in early [[automobile]]s and [[aircraft]]. J. K. Starley's company became the ''Rover Cycle Company Ltd.'' in the late 1890s, and then the ''[[Rover (car)|Rover]]'' auto maker.  The [[Morris Motor Company]] (in [[Oxford]]) and [[Škoda Auto|Škoda]] also began in the bicycle business, as did [[Henry Ford]] and the [[Wright Brothers]].
  
−
Bicycle manufacturing proved to be a training ground for other industries. Building modern bicycle frames led to the development of advanced metalworking techniques, both for the frames themselves and for special components such as [[Bearing (mechanical)|ball bearings]], [[washer (mechanical)|washer]]s, and [[sprocket]]s. These techniques later enabled skilled metalworkers and mechanics to develop the components used in early [[automobile]]s and [[aircraft]]. J. K. Starley's company became the ''Rover Cycle Company Ltd.'' in the late 1890s, and then the ''[[Rover (car)|Rover]]'' auto maker. The [[Morris Motor Company]] and [[Škoda Auto|Škoda]] also began in the bicycle business, as did [[Henry Ford]] and the [[Wright Brothers]].
+
Some bicycle clubs and national associations became prominent advocates for improvements to roads and highways. In the [[United States]], the [[League of American Wheelmen]] lobbied for the improvement of roads in the last part of the 19th century, founding and leading the national [[Good Roads Movement]]. Both their model for political organization and the paved roads for which they argued facilitated the growth of the bicycle's rival, the [[automobile]].
  
−
Some of the bicycle clubs and national associations became prominent advocates for improvements to roads and highways. In the [[United States]], the [[League of American Wheelmen]] was a prominent advocate for the improvement of roads in the last part of the 19th century, founding and leading the national [[Good Roads Movement]] in the US.
+
In recent years, US and European bicycle makers have moved much of their production to Asia. Some sixty percent of the world's bicycles are now being made in China. Despite this shift in production, as nations such as [[China]] and [[India]] become more wealthy, their own use of bicycles has declined. One of the major reasons for the proliferation of Chinese-made bicycles in foreign markets is the increasing affordability of cars and motorcycles for its own citizens.
  
−
[[Image:WhiteBikesVeluwe.jpg|thumb|250px|left|In the Netherlands, bicycles are made available for use in national parks]]The evolution of the bicycle had less tangible effects as well, extending early to areas as diverse as fashion and politics.  In the [[1890s]] the cycling craze led to a new set of fashions, including ''bloomers'', which helped liberate women from corsets and other restrictive clothing.  A British perfumer marketed ''Cycling Bouquet'', which came in a tiny vial designed to fit into a lady cyclist's purse. The diamond-frame safety bicycle gave women unprecedented mobility, contributing to their emancipation in Western nations. Sociologists suggest that bicycles enlarged the gene pool for rural workers, by enabling them to easily reach the next town and increase their ''courting radius''.  In cities, bicycles helped reduce crowding in inner-city tenements by allowing workers to commute from single-family dwellings in the suburbs. They also reduced dependence on horses, and allowed people to travel into the country, since bicycles were three times as energy efficient as walking, and three to four times as fast.  In North America, the political organization of bicycle enthusiasts, in such groups as the ''League of American Wheelmen'', led to further changes.  Both their model for political organization and the paved roads for which they argued facilitated the growth of the bicycle's rival, the [[automobile]].
+
===Female emancipation===
 +
[[Image:Woman with Bicycle 1890s.jpg|thumb|Woman with bicycle, 1890s]]
 +
The diamond-frame safety bicycle gave women unprecedented mobility, contributing to their [[Emancipation of women|emancipation]] in Western nations. As bicycles became safer and cheaper, more women had access to the personal freedom they embodied, and so the bicycle came to symbolise the [[New Woman]] of the late nineteenth century, especially in Britain and the United States.   
  
−
In recent years, US and European bicycle makers have moved much of their production to Asia. Some sixty percent of the world's bicycles are now being made in China. Despite this shift in production, as nations such as China and India become more wealthy, their own use of bicycles has declined. One of the major reasons for the proliferation of Chinese-made bicycles in foreign markets is the increasing affordability of cars and motorcycles for its own citizens <sup>[[#Notes|5]]</sup>.
+
The bicycle was recognised by nineteenth-century [[feminist]]s and [[suffragist]]s as a "freedom machine" for women.  American [[Susan B. Anthony]] said: "Let me tell you what I think of bicycling. I think it has done more to emancipate women than anything else in the world. It gives women a feeling of freedom and self-reliance. I stand and rejoice every time I see a woman ride by on a wheel...the picture of free, untrammeled womanhood." In 1895 [[Frances Willard]], the tightly-laced president of the [[Women’s Christian Temperance Union]], wrote a book called ''How I Learned to Ride the Bicycle'', in which she praised the bicycle she learned to ride late in life, and which she named "Gladys", for its "gladdening effect" on her health and political optimism.  Willard used a cycling metaphor to urge other suffragists to action, proclaiming, "I would not waste my life in friction when it could be turned into momentum."
  
 +
The male anger at the freedom symbolised by the New (bicycling) Woman was demonstrated when the male undergraduates of [[Cambridge University]] chose to show their opposition to the admission of women as full members of the university by hanging a woman in effigy in the main town square -- tellingly, a woman on a bicycle.  This was as late as 1897.[http://www.newn.cam.ac.uk/about/about_history2.shtml]
 +
 +
In the 1890s the [[bicycle craze]] led to a movement for so-called [[rational dress]], which helped liberate women from corsets and ankle-length skirts and other restrictive garments, substituting the then-shocking [[bloomers (clothing)|bloomers]].
 +
 +
===Other social implications===
 +
Sociologists suggest that bicycles enlarged the [[gene pool]] for rural workers, by enabling them to easily reach the next town and increase their ''courting radius''.  In cities, bicycles helped reduce crowding in inner-city tenements by allowing workers to commute from more spacious dwellings in the suburbs. They also reduced dependence on horses, with all the knock-on effects this brought to society.  Bicycles allowed people to travel for leisure into the country, since bicycles were three times as energy efficient as walking, and three to four times as fast.
 +
 +
==Uses for bicycles==
 
===Bicycles at work===
 
===Bicycles at work===
−
[[Image:PoliceOfficerOnBike.jpg|thumb|right|Police officer on a bicycle]]
+
[[Image:PoliceOfficerOnBike.jpg|thumb|250px|right|Police officer on a bicycle]]
  
−
The [[mail|postal service]]s of many countries have long relied on bicycles.  The [[Royal Mail]] first started using bicycles in 1880.  Bicycle delivery fleets include 37,000 in the [[UK]], 25,700 in [[Germany]] and 10,500 in [[Hungary]].  [[Police]] officers adopted the bicycle as well, initially using their own.  However, they eventually became a standard issue, particularly for police in rural areas.  The [[Kent]] police purchased 20 bicycles in 1896, and by 1904 there were 129 police bicycle patrols operating. Some countries retained the police bicycle while others dispensed with them for a time.  Bicycle patrols are now enjoying a resurgence in many cities, as the mobility of car-borne officers is becoming increasingly limited by traffic congestion and [[Auto-free zone|pedestrianisation]].  They also have the advantages that the officers are inherently more open to the public, and the transport is quieter to permit a more stealthy approach toward suspects.  The pursuit of suspects can also be assisted by a bicycle.
+
The [[mail|postal service]]s of many countries have long relied on bicycles.  The British [[Royal Mail]] first started using bicycles in 1880; now bicycle delivery fleets include 37,000 in the [[United Kingdom|UK]], 25,700 in [[Germany]] and 10,500 in [[Hungary]].  The [[London Ambulance Service]] has recently introduced bicycling paramedics, who can often get to the scene of an incident in [[Central London]] more quickly than a motorised ambulance.  
  
−
Bicycles have enjoyed substantial use as general delivery vehicles in many cities.  In the UK, this use persisted for some purposes with generations of teenagers getting their first jobs delivering newspapers by bicycle.  In [[India]], many of [[Mumbai]]'s [[Dabbawala]]s use bicycles to deliver hot lunches to the city’s workers.  In [[Bogotá]], [[Colombia]] the city’s largest bakery recently replaced most of its delivery trucks with bicycles.  Even the car industry uses bicycles.  At the huge [[Mercedes-Benz]] factory in [[Sindelfingen]], [[Germany]] workers use bicycles, colour-coded by department, to move around the factory.
+
[[Police]] officers adopted the bicycle as well, initially using their own.  However, they eventually became a standard issue, particularly for police in rural areas.  The [[Kent]] police purchased 20 bicycles in 1896, and by 1904 there were 129 police bicycle patrols operating. Some countries retained the police bicycle while others dispensed with them for a time.  Bicycle patrols are now enjoying a resurgence in many cities, as the mobility of car-borne officers is becoming increasingly limited by traffic congestion and [[Auto-free zone|pedestrianisation]].  They also have the advantages that the officers are inherently more open to the public, and the transport is quieter to permit a more stealthy approach toward suspects.  The pursuit of suspects can also be assisted by a bicycle.
  
−
===Bicycles and war===
+
[[Image:coconut_bunch.jpg|thumb|250px|left| A bicycle loaded with [[tender coconut]] for sale. [[Karnataka]], [[India]]]]
  
−
''Main article: [[Bicycle infantry]]''
+
Bicycles enjoy substantial use as general delivery vehicles in many countries.  In the UK and North America, generations of teenagers have got their first jobs delivering newspapers by bicycle.  London has many delivery companies that use bicycles with trailers. Most cities in the West, and many outside it, support a sizable and visible industry of [[Bicycle messenger|cycle couriers]] who deliver documents and small packages.  In [[India]], many of [[Mumbai]]'s [[Dabbawala]]s use bicycles to deliver hot lunches to the city’s workers.  In [[Bogotá]], [[Colombia]] the city’s largest bakery recently replaced most of its delivery trucks with bicycles.  Even the car industry uses bicycles.  At the huge [[Mercedes-Benz]] factory in [[Sindelfingen]], [[Germany]] workers use bicycles, colour-coded by department, to move around the factory.
  
−
The bicycle is not suited for combat, but it has been used as a method of transporting soldiers and supplies to combat zones. Bicycles were used in the [[Second Boer War]], where both sides used them for scouting. In [[World War I]], France and Germany used bicycles to move troops. In its [[1937]] invasion of China, Japan employed some 50,000 bicycle troops, and similar forces were instrumental in Japan's march through [[Malaya]] in [[World War II]].  Germany used bicycles again in World War II, while the British employed airborne ''Cycle-commandos'' with folding bikes.
+
===Bicycle recreation===
 +
[[Image:WhiteBikesVeluwe.jpg|thumb|250px|right|In the Netherlands, bicycles are made available for use in national parks]]
  
−
In the [[Vietnam War]], communist forces used bicycles extensively as cargo carriers along the [[Ho Chi Minh Trail]]. There are reports of mountain bicycles being used in scouting by U.S. Special Forces in the [[U.S. invasion of Afghanistan]] and in subsequent battles against the [[Taliban]]. The only country to recently maintain a regiment of bicycle troops was [[Switzerland]], who disbanded the last unit in [[2003]].
+
Bicycles are used for recreation at all ages. [[Bicycle touring]], also known as cyclotourism, involves touring and exploration or sightseeing by bicycle for leisure. A [[brevet (cycling)|brevet]] or randonnée is an organized long-distance ride.
  
−
=== Bicycle racing ===
+
One aspect of [[Netherlands|Dutch]] popular culture is enjoying relaxed cycling in the [[rural|countryside]] of the [[Netherlands]]. The land is very flat and full of public bicycle trails where cyclist aren't bothered by [[automobile|cars]] and other traffic, which makes it ideal for cycling [[recreation]]. Many [[Dutch people]] subscribe every [[year]] to an event called ''[[fietsvierdaagse]]'' &mdash; four days of organised cycling through the local environment. [[Paris-Brest-Paris]] (PBP), which began in 1891, is the oldest bicycling event still run on a regular basis on the open road, covers over 1200 km and imposes a 90-hour time limit.
  
−
''Main article: [[Bicycle racing]]''
+
===Bicycles and war===
 +
{{main|bicycle infantry}}
  
−
Shortly after the introduction of bicycles, competitions developed independently in many parts of the world. Early races involving boneshaker style bicycles were predictably fraught with injuries. Large races became popular during the 1890's "Golden Age of Cycling", with events across Europe, and in the U.S. and Japan as well. [[Paris-Brest-Paris]] (PBP), which began in [[1891]], is the oldest bicycling event still run on a regular basis on the open road, covers over 1200 km and imposes a 90-hour time limit. The most famous of all bicycle races, and perhaps the most well-known race of any type, is the [[Tour de France]].  This began in [[1903]], and continues to capture the attention of the sporting world.
+
The bicycle is not suited for combat, but it has been used as a method of transporting soldiers and supplies to combat zones. Bicycles were used in the [[Second Boer War]], where both sides used them for scouting. In [[World War I]], France and Germany used bicycles to move troops. In its 1937 invasion of China, Japan employed some 50,000 bicycle troops, and similar forces were instrumental in Japan's march through [[Malaya]] in [[World War II]].  Germany used bicycles again in World War II, while the British employed airborne ''Cycle-commandos'' with folding bikes.
  
−
As the bicycle evolved its various forms, different racing formats developed.  Road races may involve both team and individual competition, and are contested in various ways. They range from the one-day road race, [[criterium]], and time trial to multi-stage events like the Tour de France and its sister events which make up cycling's [[Grand Tour (cycling)|Grand Tours]]. [[Recumbent bicycle]]s were banned from bike races in 1934 after [[Marcel Berthet]] set a new [[hour record]] in his ''Velodyne streamliner'' (49.992 km on Nov 18, 1933). [[Velodrome]]s host short course [[track cycling]] which features mostly [[fixed-gear bicycle]]s, while [[cyclo-cross]] races are held on rugged outdoor terrain.  In the past decade, [[mountain biking|mountain bike racing]] has also reached international popularity and is even an Olympic sport.
+
In the [[Vietnam War]], communist forces used bicycles extensively as cargo carriers along the [[Ho Chi Minh Trail]]. There are reports of mountain bicycles being used in scouting by U.S. Special Forces in the [[U.S. invasion of Afghanistan]] and in subsequent battles against the [[Taliban]]. The only country to recently maintain a regiment of bicycle troops was [[Switzerland]], who disbanded the last unit in 2003.
  
−
=== Modal share: cycle use in modern cities ===
+
===Bicycle racing===
 +
{{main|bicycle racing}}
  
−
Cyclists and motorists make different demands on road design which may lead to conflicts both in politics and on the streets.  Some jurisdictions give priority to motorised traffic, for example setting up extensive one-way street systems, free-right turns, high capacity roundabouts, and slip roads. Other cities may apply active ''traffic restraint'' measures to limit the impact of motorised transport.  In the former cases, cycling has tended to decline while in the latter it has tended to be maintained.  Occasionally, extreme measures against cycling may occur. In [[Shanghai]], a city where bicycles were once the dominant mode of transportation, bicycle travel on city roads was actually banned temporarily in December [[2003]].
+
Shortly after the introduction of bicycles, competitions developed independently in many parts of the world. Early races involving boneshaker style bicycles were predictably fraught with injuries. Large races became popular during the 1890's "Golden Age of Cycling", with events across Europe, and in the U.S. and Japan as well.  At one point, almost every major city in the US had a [[velodrome]] or two for [[track racing]] events. However since the middle of the 20th Century cycling has become a minority sport in the US whilst in Continental Europe it continues to be a major sport, particularly in France, Belgium and Italy. The most famous of all bicycle races is the [[Tour de France]].  This began in 1903, and continues to capture the attention of the sporting world.
  
−
In areas in which cycling is popular and encouraged, cycle-parking facilities using [[bicycle rack]]s, lockable ''mini-garages'', and patrolled cycle parks are used to reduce theft.  Local governments also promote cycling by permitting the carriage of bicycles on public transport or by providing external attachment devices on public transport vehicles.  Conversely, an absence of secure cycle-parking is a recurring complaint by cyclists from cities with low modal share of cycling.
+
As the bicycle evolved its various forms, different racing formats developed.  Road races may involve both team and individual competition, and are contested in various ways. They range from the one-day road race, [[criterium]], and time trial to multi-stage events like the Tour de France and its sister events which make up cycling's [[Grand Tour (cycling)|Grand Tours]]. [[Recumbent bicycle]]s were banned from bike races in 1934 after [[Marcel Berthet]] set a new [[hour record]] in his ''Velodyne streamliner'' (49.992 km on Nov 18, 1933). [[Track bicycle]]s are used for [[Track cycling|track racing]] in [[Velodrome]]s , while [[cyclo-cross]] races are held on rugged outdoor terrain.  In the past decade, [[mountain biking|mountain bike racing]] has also reached international popularity and is even an Olympic sport.
  
−
Extensive [[bicycle path]] systems may be found in some cities. Such dedicated paths often have to be shared with inline skaters, scooters, skateboarders, and pedestrians. Segregating bicycle and automobile traffic in cities has met with mixed success, both in terms of safety and bicycle promotion.  At some point the two streams of traffic inevitably intersect, often in a haphazard and congested fashion. Studies have demonstrated that, due to the high incidence of accidents at these sites, such segregated schemes can actually ''increase'' the number of car-bike collisions.<sup>[[#Notes|7]]</sup>
+
The governing body of international cycle sport, the [[Union Cycliste Internationale]], decided in the late 1990s to create additional rules restricting the design of racing bicycles. These rules met with considerable controversy and to some extent arrested the development of the racing bicycle. Their stated motive was so that developing countries could compete in international competitions without requiring large equipment budgets, and to re-focus attention on the athlete rather than the bicyle. For example, [[monocoque]] frames, such as used by Chris Boardman to win the Gold medal in 1992 Olympic individual pursuit event in Barcelona, were no longer permitted.
  
−
===Bicycle activism===
+
===Modal share: cycle use in modern cities===
−
Cyclists of many types form associations, both for specific interests (trails development, road maintenance, urban design, racing clubs, touring clubs, etc.) and for more global goals ([[energy conservation]], pollution reduction, promotion of fitness).  There tend to be two broad themes associated with bicycle activism:  one strand of opinion tends to be more overtly political and frequently has roots in the [[environmental movement]], while the other tends to draw on the traditions of the established bicycle lobby.
+
{{main|utility cycling}}
  
−
Such groups may promote the bicycle as an alternative mode of transport and may also emphasize the potentials for energy and resource conservation and potential health benefits gained through a modal shift to cycle use from automobile use. Activists in both main camps tend also to argue for improved local and inter-city rail services and other methods of mass transportation, and also for greater provision for cycle carriage on such services.
+
Cyclists and motorists make different demands on road design which may lead to conflicts both in politics and on the streets.  Some jurisdictions give priority to motorised traffic, for example setting up extensive one-way street systems, free-right turns, high capacity roundabouts, and slip roads.  Other cities may apply active ''traffic restraint'' measures to limit the impact of motorised transport. In the former cases, cycling has tended to decline while in the latter it has tended to be maintained.  Occasionally, extreme measures against cycling may occur.  In [[Shanghai]], a city where bicycles were once the dominant [[mode of transportation]], bicycle travel on city roads was actually banned temporarily in December 2003.
  
−
Controversially, some bicycle activists and some traffic management advisors seek the construction of [[segregated cycle facilities]] for journeys of all lengths. Activists from the more established tradition tend to view such devices with suspicion and favour a more holistic approach based on planning, road design, road user education and enforcement of the existing traffic regulations.  The opposition to segregated cycle facilities has well-founded historical roots regarding the safety, practicality and intent of such systems. However, in some cases this opposition has a more ideological basis: some members of the US [[Effective Cycling|Vehicular Cycling Movement]] oppose the use of segregated cycling facilities as a matter of principle<sup>[[#Notes|8]]</sup>, and offer training courses aimed at the safe integration of cyclists into everyday urban traffic.  This is part of the ongoing [[cycle path debate]].
+
In areas in which cycling is popular and encouraged, cycle-parking facilities using [[bicycle rack]]s, lockable ''mini-garages'', and patrolled cycle parks are used to reduce theft.  Local governments also promote cycling by permitting the carriage of bicycles on public transport or by providing external attachment devices on public transport vehicles. Conversely, an absence of secure cycle-parking is a recurring complaint by cyclists from cities with low modal share of cycling.
  
−
A recent focus, especially for European bicycle activists, has been opposition to compulsory [[bicycle helmet]] legislation. Their concerns have been raised by evidence suggesting that compulsory helmet laws and helmet promotion have been associated with significant reductions in bicycle use and with simultaneous increases in the risk of death or injury to individual cyclists. As a consequence, activists from both sides have put aside their differences in order to fight the helmet lobby.
+
Extensive [[bicycle path]] systems may be found in some cities. Such dedicated paths often have to be shared with inline skaters, scooters, skateboarders, and pedestrians. Segregating bicycle and automobile traffic in cities has met with mixed success, both in terms of safety and bicycle promotion.  At some point the two streams of traffic inevitably intersect, often in a haphazard and congested fashion. Studies have demonstrated that, due to the high incidence of accidents at these sites, such segregated schemes can actually ''increase'' the number of car-bike collisions.
  
−
[[Critical Mass]] is a worldwide activist movement of mass bicycle protest rides that may have more overt political overtones. While this anarchic movement is difficult to typify, it tends to incorporate the themes of increasing the road- and mind-share given by society to bicycle transport, and has historically drawn support from environmentally minded campaigners as well as many other more diverse strands of political thought. However, the particular forms of protest embraced by Critical Massers has drawn criticism from the broader streams of activism.
 
  
−
==Types of bicycle==
+
===Cycling activism===
  
−
There are many different types of bicycle. See also [[:Category:Cycle types]].
+
Cyclists form associations, both for specific interests (trails development, road maintenance, urban design, racing clubs, touring clubs, etc.) and for more global goals ([[energy conservation]], pollution reduction, promotion of fitness).  Two broad themes run in bicycle activism:  one more overtly political with roots in the [[environmental movement]]; the other drawing on the traditions of the established bicycle lobby.
  
−
====By function====
+
Such groups promote the bicycle as an alternative mode of transport and emphasize the potential for energy and resource conservation and health benefits gained from cycling versus automobile use. Activists in both camps  also argue for improved local and inter-city rail services and other methods of mass transportation, and also for greater provision for cycle carriage on such services. Many cities also have [[community bicycle program]]s that promote cycling, especially as a means of inner-city transport.
−
* ''[[Mountain bicycle]]s'' are designed for off-road cycling, and include other sub-types of off-rad bicycles such as Cross Country (i.e."XC"), Downhill , and to a lesser extent Freeride bicycles. All mountain bicycles feature sturdy, highly durable frames and wheels, wide-gauge treaded tires, and cross-wise handlebars to help the rider resist sudden jolts. Some mountain bicycles  feature various types of suspension systems (e.g. coiled spring, air or gas shock), and hydraulic or mechanical disc brakes. Mountain bicycle gearing is very wide-ranging, from very low ratios to high ratios. Modern mountain bicycles typicaly have 21 to 30 gears.
+
[[Image:Critical Mass, San Francisco, April 29, 2005.jpg|thumb|left|300px|San Francisco [[Critical Mass]], 29th April, 2005.]]
−
* ''[[Racing bicycle]]s'' are designed for speed, and include Road, Time Trial, and Track bicycles. They have lightweight frames and components with minimal accessories, ''dropped'' handlebars to allow for an aerodynamic riding position, narrow high-pressure tires for minimal rolling resistance and multiple gears. Racing bycycles have a relatively narrow gear range, and typically varies from medium to very high ratios, distributed across 18, 20, 27 or 30 gears. The narrow gear ratios allow racers to fine tune their gear selection so as to produce an efficient pedalling cadence.  
+
Controversially, some bicycle activists (including some traffic management advisors) seek the construction of [[segregated cycle facilities]] for journeys of all lengths. Other activists, especially those from the more established tradition, view the safety, practicality, and intent of many [[segregated cycle facilities]] with suspicion. They favour a more holistic approach based on [[Traffic psychology#Accident prevention and improvement of traffic safety|the 4 'E's]]; ''education'' (of everyone involved), ''encouragement'' (to apply the education), ''enforcement'' (to protect the rights of others), and ''engineering'' (to facilitate travel while respecting every person's equal right to do so). In some cases this opposition has a more ideological basis: some members of the [[Vehicular cycling|Vehicular Cycling movement]] oppose segregated public facilities, such as on-street [[segregated cycle facilities|bike lanes]], on principle. Some groups offer [[Vehicular cycling#VC Education|training courses]] to help cyclists integrate themselves with other traffic. This is part of the ongoing [[cycle path debate]].
  
−
Time Trial bicycles are similar to Road bicycles but are differentiated by a more aggresive frame geometry that throws the rider   
+
[[Critical Mass]] is a worldwide activist movement of mass bicycle protest rides. It incorporates the themes of increasing the road- and mind-share given to bicycle transport, and has drawn support from environmentally minded campaigners and other schools of political thought. According to participants in Critical Mass, "We aren't blocking traffic, we ''are'' traffic!" However, their particular forms of protest has drawn criticism from the broader streams of activism.
−
to a more compact (i.e "aero") riding position. They also feature aeroynamic frames, wheels, and handlebars.  
 
  
−
Track bicycles, a form of racing bicycle intended for indoor racing circuits, are exceptionally simplified to reduce weight. They typically have a single gear mounted to a fixed hub (i.e. no freewheel), no brakes, and are minimally adorned with other components that would otherwise be typical for a racing bicycle.
+
There is a long-running [[Bicycle_helmet#The_helmet_debate | cycle helmet debate]] among activists. The most heated controversy surrounds the topic of [[Bicycle_helmet#Use.2C_promotion.2C_compulsion | compulsory helmet use]].
  
−
Messenger Bike, like the track bike, in regards to no gears(fixed gear) and no brakes, but riden by messengers hussling packages for law firms, advertising firms, sandwich shops, big banks, etc.  You may identify these persons by "reckless" operation of a bike, rudeness, and general disregard to others. Yes thats how we like it....  But the bike itself is fun to ride, and you actually become one with the bicycle.  Your muscle is used to stop the momentum it has gained by using muscle.  just like riding a tricycle when you were a kid. These bikes are easy to maintain as well.  Also not very big on being stolen.... not a lot of people know how to ride a fixed gear bike.
+
==Types of bicycle==
 +
There are many different types of bicycle. See also [[:Category:Cycle types]].
  
 +
====By function====
 +
[[Image:Stanford-bikes.jpg|[[Utility bicycle]]s parked outside an academic building at [[Stanford University]]|thumb|right|250px]]
 +
* ''[[Utility bicycle]]s'' are designed for [[Bicycle commuting|commuting]], [[utility cycling|shopping and running errands]]. They employ middle or heavy weight frames and tires, internal [[hub gear]]ing, and a variety of helpful accessories. The riding position is usually upright.
 +
* ''[[Mountain bicycle]]s'' are designed for off-road cycling, and include other sub-types of off-road bicycles such as Cross Country (i.e."XC"), Downhill , and to a lesser extent Freeride bicycles. All mountain bicycles feature sturdy, highly durable frames and wheels, wide-gauge treaded tires, and cross-wise handlebars to help the rider resist sudden jolts. Some mountain bicycles feature various types of suspension systems (e.g. coiled spring, air or gas shock), and hydraulic or mechanical disc brakes. Mountain bicycle gearing is very wide-ranging, from very low ratios to high ratios, typicaly with 21 to 30 gears.
 +
* ''[[Racing bicycle]]s'' are designed for speed, and include road, time trial, and track bicycles. They have lightweight frames and components with minimal accessories, ''dropped'' handlebars to allow for an aerodynamic riding position, narrow high-pressure tires for minimal rolling resistance and multiple gears. Racing bicycles have a relatively narrow gear range, and typically varies from medium to very high ratios, distributed across 18, 20, 27 or 30 gears. The more closely spaced gear ratios allow racers to choose a gear which will enable them to ride at their optimun pedaling cadence for maximum efficency.
 +
** ''[[Time trial bicycle]]s'' are similar to road bicycles but are differentiated by a more aggressive frame geometry that throws the rider into a more compact (i.e "aero") riding position. They also feature aerodynamic frames, wheels, and handlebars.
 +
** ''[[Track bicycle]]s'', intended for indoor or outdoor cycle tracks or [[velodrome]]s, are exceptionally simple compared with road bikes. They have a single gear ratio, a fixed drivetrain (i.e. no freewheel), no brakes, and are minimally adorned with other components that would otherwise be typical for a racing bicycle.
 +
* Messenger bikes are typically used for urgent deliveries of letters and small packages between businesses in big cities with heavily congested traffic. While any bike can be used, messenger bikes often resemble track bicycles (especially in the USA).
 
[[Image:Bike refelector safety flash.JPG|thumb|A modern ''touring bicycle'', with accessories and baggage]]
 
[[Image:Bike refelector safety flash.JPG|thumb|A modern ''touring bicycle'', with accessories and baggage]]
−
 
+
* ''[[Touring bicycle]]s'' are designed for [[bicycle touring]] and long journeys. They are durable and comfortable, capable of transporting baggage, and may feature any type of gearing system.
 
* ''[[Randonneur]]'' or ''Audax bicycles'' are designed for [[randonnée]]s or brevet rides, and fall in between racing bicycles and those intended for touring.
 
* ''[[Randonneur]]'' or ''Audax bicycles'' are designed for [[randonnée]]s or brevet rides, and fall in between racing bicycles and those intended for touring.
−
* ''[[Touring bicycle]]s'' are designed for [[bicycle touring]] and long journeys. They are durable and comfortable, capable of transporting baggage, and may feature any type of gearing system.
+
* ''[[Recumbent bicycle]]s'', which are sometimes referred to as ''Bents'' in the USA, are designed to maximise comfort and minimise wind resistance. Whereas most of the other types of bicycle in this section are designed around a ‘diamond frame’ geometary, where the pedals and chainset are located at the bottom of the bicycle and handlebars are at the front, recumbent bicycles (recumbents) generally use a “boom” and rear triangle combination with the pedals and chainset located at the front of the boom and the handlebars are located either “over seat” or “underseat” in the centre.
−
* ''[[Utility bicycle]]s'' are designed for commuting, shopping and running errands. They employ middle or light weight frames and tires, internal [[hub gear]]ing, and a variety of helpful accessories.
 
  
 
====By number of riders====
 
====By number of riders====
 
* A ''[[tandem bicycle|tandem]]'' or ''twin'' has two riders.
 
* A ''[[tandem bicycle|tandem]]'' or ''twin'' has two riders.
 
* A ''triplet'' has three riders; a ''quadruplet'' has four.
 
* A ''triplet'' has three riders; a ''quadruplet'' has four.
−
* The largest ''multi-bike'' had 40 riders.
+
* The largest ''multi-bike'' had 40 riders.[http://www.4to40.com/recordbook/index.asp?category=&counter=149]
  
−
In most of these types the riders ride one behind the other. Exceptions are "The Companion", or "sociable," a side-by-side two-person bike (that converted to a single-rider) built by the Punnett Cycle Mfg. Co. in Rochester, N. Y. in the 1890s. Another bicycle rented to tourists in [[Berlin]] carries eight people seated in a circle.
+
In most of these types the riders ride one behind the other. Exceptions are "The Companion", or "sociable," a side-by-side two-person bike (that converted to a single-rider) built by the Punnett Cycle Mfg. Co. in Rochester, N. Y. in the 1890s. Another bicycle, the "Conference Bike", rented to tourists in [[Berlin]] carries seven people seated in a circle.
  
 
====By general construction====
 
====By general construction====
Line 229: Line 231:
 
* ''[[Retro-Direct]] bicycles'' have two [[sprockets]] on the rear wheel.  By backpedaling, the secondary, usually lower, gear is engaged.
 
* ''[[Retro-Direct]] bicycles'' have two [[sprockets]] on the rear wheel.  By backpedaling, the secondary, usually lower, gear is engaged.
  
−
[[Image:Velo acrobatique 2.jpg|thumb|[[Flatland_BMX|Flatland]] rider on a BMX bike]]
+
[[Image:Velo acrobatique 2.jpg|thumb|[[Flatland_BMX|Flatland]] rider on a [[BMX]] bike]]
 
====By sport====
 
====By sport====
 
* ''[[Track bicycle]]s'' are ultra-simple, lightweight [[Fixed-gear bicycle|fixed-gear]] bikes with no brakes, designed for [[track cycling]] on purpose-built cycle tracks, often in [[velodrome]]s.
 
* ''[[Track bicycle]]s'' are ultra-simple, lightweight [[Fixed-gear bicycle|fixed-gear]] bikes with no brakes, designed for [[track cycling]] on purpose-built cycle tracks, often in [[velodrome]]s.
Line 235: Line 237:
 
* ''[[Cyclo-cross]] bicycles'' are lightweight enough to be carried over obstacles, and robust enough to be cycled through mud.
 
* ''[[Cyclo-cross]] bicycles'' are lightweight enough to be carried over obstacles, and robust enough to be cycled through mud.
 
* ''Down-hill racers'' are a specialized type of mountain bike with a very strong frame, altered geometry, and long travel suspension. They are designed for use only on downhill tracks.
 
* ''Down-hill racers'' are a specialized type of mountain bike with a very strong frame, altered geometry, and long travel suspension. They are designed for use only on downhill tracks.
−
* ''[[BMX]]'' (bicycle motocross) bicycles have small wheels and are used for [[BMX racing]], as well as for [[wheelie]]s, jumps, and other acrobatics.
+
* ''[[BMX]]'' (bicycle motocross) bicycles have small wheels and are used for [[BMX racing]], as well as freestyle with tricks such as [[wheelie]]s. Freestyle BMXers often ride dirt jumps and skatepark ramps.
 
* ''[[Triathlon]]'' bicycles have seat posts that are closer to vertical than the seat posts on road racing bicycles. This concentrates the effort of cycling in the [[quadriceps]] muscles, sparing the other large muscles of the leg for the running segment of the race. Triathlon bicycles also have specialized handlebars known as [[triathlon bars]] or aero bars.
 
* ''[[Triathlon]]'' bicycles have seat posts that are closer to vertical than the seat posts on road racing bicycles. This concentrates the effort of cycling in the [[quadriceps]] muscles, sparing the other large muscles of the leg for the running segment of the race. Triathlon bicycles also have specialized handlebars known as [[triathlon bars]] or aero bars.
  
Line 242: Line 244:
 
* A ''hand-cranked bicycle'' is driven by a hand crank.
 
* A ''hand-cranked bicycle'' is driven by a hand crank.
 
* A ''rowing bicycle'' is driven by a rowing action using both arms and legs.
 
* A ''rowing bicycle'' is driven by a rowing action using both arms and legs.
−
* An ''[[Motorized bicycle]]'' assists the rider with a powered motor.
+
* A ''[[Motorized bicycle]]'' provides motor assistance.
 
* A ''[[moped]]'' propels the rider with a motor, but includes bicycle pedals for human propulsion.
 
* A ''[[moped]]'' propels the rider with a motor, but includes bicycle pedals for human propulsion.
−
* ''Shaft drive'' bicycles connect the pedals to the rear hub with a shaft instead of a chain.
 
 
* a "Flywheel" uses stored kinetic energy.
 
* a "Flywheel" uses stored kinetic energy.
  
 
====Other types====
 
====Other types====
−
* ''[[Hybrid bicycle]]s'' are a compromise between the mountain and racing style bicycles which replaced European-style ''utility bikes'' in North America in the early [[1990]]s. They have a light frame, medium gauge wheels, and derailleur gearing, and feature straight or curved-back, ''touring'' handlebars for more upright riding.
+
* ''[[Hybrid bicycle]]s'' are a compromise between the mountain and racing style bicycles which replaced European-style ''utility bikes'' in North America in the early 1990s. They have a light frame, medium gauge wheels, and derailleur gearing, and feature straight or curved-back, ''touring'' handlebars for more upright riding.
 
* ''[[Cruiser bicycle]]s''  are designed for comfort, with curved back handlebars, padded seats, and ''balloon'' tires.  Cruisers typically have minimal gearing and are often available for rental at beaches and parks which feature flat terrain.
 
* ''[[Cruiser bicycle]]s''  are designed for comfort, with curved back handlebars, padded seats, and ''balloon'' tires.  Cruisers typically have minimal gearing and are often available for rental at beaches and parks which feature flat terrain.
 
* ''[[Freight bicycle]]s'' are designed for transporting large or heavy loads.
 
* ''[[Freight bicycle]]s'' are designed for transporting large or heavy loads.
 
* ''[[Cycle rickshaw]]s'' (also called ''pedicabs'' or ''trishaws'') are used to transport passengers for hire.
 
* ''[[Cycle rickshaw]]s'' (also called ''pedicabs'' or ''trishaws'') are used to transport passengers for hire.
 
* ''[[Velomobile]]s'' or ''bicycle cars'' provide enclosed pedal-powered transportation.
 
* ''[[Velomobile]]s'' or ''bicycle cars'' provide enclosed pedal-powered transportation.
−
* ''[[Clown bike]]s are designed for comedic effect or stunt riding. Some types of clown bicycles are:
+
* ''[[Clown bicycle]]s are designed for comedic effect or stunt riding. Some types of clown bicycles are:
 
** ''bucking bike'' (with one or more eccentric wheels)  
 
** ''bucking bike'' (with one or more eccentric wheels)  
−
**''tall bike'' (often called an ''upside down bike'', constructed so that the pedals, seat and handlebars are all higher than normal) -- other types tall bikes are made by welding two more more bicycle frames on top of each other, and running additional chains from the pedals to the rear wheel.
+
**''[[tall bike]]'' (often called an ''upside down bike'', constructed so that the pedals, seat and handlebars are all higher than normal) -- other types of tall bikes are made by welding two or more bicycle frames on top of each other, and running additional chains from the pedals to the rear wheel.
 
**''Come-apart bike'', (essentially a unicycle, plus a set of handlebars attached to forks and a wheel).
 
**''Come-apart bike'', (essentially a unicycle, plus a set of handlebars attached to forks and a wheel).
−
::Clown bikes are also built that are directly geared, with no freewheeling, so that they may be pedaled backwards. Some are built very small but are otherwise normal.
+
:Clown bikes are also built that are directly geared, with no freewheeling, so that they may be pedaled backwards. Some are built very small but are otherwise normal.
−
 
 
 
* [[Art bike]]s: Some bikes are built so that the frame appears to be made of junk or found objects: [[Bongo the Clown]] built several ridable parade bikes which were as much kinetic sculptures as transport.
 
* [[Art bike]]s: Some bikes are built so that the frame appears to be made of junk or found objects: [[Bongo the Clown]] built several ridable parade bikes which were as much kinetic sculptures as transport.
−
 
 
* A ''[[unicycle]]'' is not a bicycle, as it has only one wheel, but it is related.
 
* A ''[[unicycle]]'' is not a bicycle, as it has only one wheel, but it is related.
  
 
==Standards==
 
==Standards==
−
 
 
A number of formal and industry standards exist for bicycle components, to help make spare parts exchangeable:
 
A number of formal and industry standards exist for bicycle components, to help make spare parts exchangeable:
  
 
* [[ISO 5775]] Bicycle tire and rim designations
 
* [[ISO 5775]] Bicycle tire and rim designations
 
* ISO 8090 Cycles &mdash; Terminology (same as BS 6102-4)
 
* ISO 8090 Cycles &mdash; Terminology (same as BS 6102-4)
 +
* ISO 4210 Cycles &mdash; Safety requirements for bicycles
  
−
== See also ==
+
==See also==
 +
[[Image:Bicycles snow Graz 2005 original.jpg|thumb|250px|Bicycles in the snow]]
 +
* [[Bicycle gearing]]
 +
* [[Trampe bicycle lift|Bicycle lift]]
 +
* [[Bicycle lighting]]
 
* [[Bicycle lock]]
 
* [[Bicycle lock]]
 
* [[Bicycle messenger]]
 
* [[Bicycle messenger]]
 +
* [[Bicycle performance]]
 +
* [[Bicycle and motorcycle dynamics]]
 +
* [[Bicycle safety]]
 +
* [[Bicycling terminology]]
 +
* [[Bicycle trailer]]
 +
* [[Clothing-optional bike rides]]
 
* [[Clown bicycle]]  
 
* [[Clown bicycle]]  
 
* [[Countersteering]]
 
* [[Countersteering]]
 +
* [[Cycle rickshaw]]
 
* [[Cycling]]
 
* [[Cycling]]
 
* [[Cycling hand signals]]
 
* [[Cycling hand signals]]
 +
* [[Fietsvierdaagse]]
 
* [[French bicycle industry]]
 
* [[French bicycle industry]]
 
* [[List of bicycle manufacturers]]
 
* [[List of bicycle manufacturers]]
 
* [[List of environment topics]]
 
* [[List of environment topics]]
 
* [[List of important cycling events]]
 
* [[List of important cycling events]]
 +
* [[Motorcycles]]
 
* [[Mountain biking]]
 
* [[Mountain biking]]
−
* [[Quadricycle]]
+
* [[Quadricycle]]
−
* [[Raleigh Chopper]]
+
* [[Racing bicycle]]
 +
* [[Raleigh Chopper]]
 +
* [[Recumbent bicycle]]
 
* [[Segregated cycle facilities]]
 
* [[Segregated cycle facilities]]
−
* [[Safety standards]]
+
* [[Safety standards]]
 +
* [[Tandem bicycle]]
 
* [[Timeline of transportation technology]]
 
* [[Timeline of transportation technology]]
 
* [[Tricycle]]
 
* [[Tricycle]]
−
* [[Urban bicycling]]
+
* [[Utility cycling]]
 
* [[Vehicular cycling]]
 
* [[Vehicular cycling]]
  
−
==Notes==
+
 
−
*1 [[Scientific American]], March 1973: "Bicycle Technology", by S.S.Wilson.
 
−
*2 [http://www.jhu.edu/~gazette/1999/aug3099/30pedal.html "Johns Hopkins Gazette", Aug.30, 1999]
 
−
*3 "The Stability of the Bicycle", David Jones, "Physics Today", April 1970: pp.34-40 (external link, below)
 
−
*4 Townsend (external link, below)
 
−
*5 [[The Economist]], Feb.15, 2003
 
−
*6 "Cities for Cyclists" (external link, below)
 
−
*7 "Bicycling Life"  (external link, below)
 
−
*8 "John Forester's Effective Cycling"  (external link, below)
 
−
*9 See Chapter 9 of "Bicycling Science" (Reference, below) for details of transmission efficiency.
 
  
 
==References==
 
==References==
−
{{wikibookspar||Bicycle repair}}
+
 
 
* ''All About Bicycling'', Rand McNally.
 
* ''All About Bicycling'', Rand McNally.
−
* ''The New Columbia Encyclopedia''
 
 
* Richard Ballantine, ''Richard's Bicycle Book'', Pan, 1975.
 
* Richard Ballantine, ''Richard's Bicycle Book'', Pan, 1975.
 
* Caunter C. F. ''The History and Development of Cycles'' Science Museum London 1972.
 
* Caunter C. F. ''The History and Development of Cycles'' Science Museum London 1972.
Line 311: Line 316:
 
* David B. Perry, ''Bike Cult: the Ultimate Guide to Human-powered Vehicles'', Four Walls Eight Windows, 1995.
 
* David B. Perry, ''Bike Cult: the Ultimate Guide to Human-powered Vehicles'', Four Walls Eight Windows, 1995.
 
* Roni Sarig, ''The Everything Bicycle Book'', Adams Media Corporation, 1997
 
* Roni Sarig, ''The Everything Bicycle Book'', Adams Media Corporation, 1997
−
* {{Web reference | title=Randonneurs USA | work=PBP: Paris-Brest-Paris | URL=http://www.rusa.org/pbp.html | date=March 31 | year=2005}}
 
 
*US Department of Transportation, Federal Highway Administration. "America's Highways 1776-1976", pp. 42-43. Washington, DC, US Government Printing Office.
 
*US Department of Transportation, Federal Highway Administration. "America's Highways 1776-1976", pp. 42-43. Washington, DC, US Government Printing Office.
 
* David Gordon Wilson, ''Bicycling Science'', MIT press, ISBN 0-262-73154-1
 
* David Gordon Wilson, ''Bicycling Science'', MIT press, ISBN 0-262-73154-1
 +
* David V. Herlihy, ''Bicycle: The History'', Yale University Press, 2004
 +
* Frank Berto, ''The Dancing Chain: History and Development of the Derailleur Bicycle'', San Francisco: Van der Plas Publications, 2005, ISBN 1-892495-41-4.
 +
* ''The Data Book: 100 Years of Bicycle Component and Accessory Design'', San Francisco: Van der Plas Publications, 2005, ISBN 1-892495-01-5.
  
 
==External links==
 
==External links==
−
{{commonscat|Bicycle}}
+
 
 
* The World's Bicycle Conference:  [http://www.velomondial.net Velo Mondial]
 
* The World's Bicycle Conference:  [http://www.velomondial.net Velo Mondial]
−
* The World's Data Base for Cycling Expertise: [http://www.velo.info Velo.Info ]
 
−
* BikeForums.net (2005). [http://www.bikeforums.net/ BikeForums]. Retrieved March 30, 2005.
 
 
* [http://sheldonbrown.com/ Brown, Sheldon] (2005). Extensive online [http://sheldonbrown.com/glossary.html bicycle glossary].
 
* [http://sheldonbrown.com/ Brown, Sheldon] (2005). Extensive online [http://sheldonbrown.com/glossary.html bicycle glossary].
−
* Bryan (2004). [http://www.battewell.freeserve.co.uk/bike.html Bryan's Bicycle Page]. Retrieved March 30, 2005.
 
−
* Croydon Cycling Campaign (2003). [http://www.croydon-lcc.org.uk/info/help.htm Information & Help]. Retrieved March 30, 2005.
 
 
* eHow, Inc. (2005). [http://www.ehow.com/how_228_make-bike-fit.html  How to Make Your Bike the Perfect Fit]. Retrieved March 30, 2005.
 
* eHow, Inc. (2005). [http://www.ehow.com/how_228_make-bike-fit.html  How to Make Your Bike the Perfect Fit]. Retrieved March 30, 2005.
−
* Learn to Bicycle (2005). [http://www.tc.umn.edu/~hause011/article/Learn_to_Ride_Bike.html Learn to Bike, no training wheels].
+
* [http://www.ecf.com/ European Cyclists' Federation]
−
* European Cyclists' Federation (2002). [http://www.ecf.com/networks/net_cities1.htm  Cities for Cyclists]. Retrieved March 30, 2005.
 
 
* Exploratorium (2004). [http://www.exploratorium.edu/cycling/humanpower1.html Science of Cycling: Human Power]. Retrieved March 30, 2005.
 
* Exploratorium (2004). [http://www.exploratorium.edu/cycling/humanpower1.html Science of Cycling: Human Power]. Retrieved March 30, 2005.
−
*  [http://www.atob.org.uk Folding bikes, electric bikes, trailers, trikes and alternative transport] Retrieved June 5, 2005
+
* Hudson, William (2003). [http://www.jimlangley.net/ride/bicyclehistorywh.html Myths and Milestones in Bicycle Evolution]. Retrieved March 30, 2005.
−
* Gray Matter Media (1995). [http://www.synaptic.bc.ca/ejournal/BicycleTouringResources.htm The eJournal website Bicycle Touring Central]. Retrieved March 30, 2005.
 
−
* Hashmi, Khurram (2004). [http://www.khurramweb.com/safety.html Bicycle Safety:  Road Hazards, Accident Prevention and Risk Mitigation]. Retrieved March 30, 2005.
 
−
* Hudson, William (2003). [http://www.jimlangley.net/ride/bicyclehistorywh.html/ Myths and Milestones in Bicycle Evolution]. Retrieved March 30, 2005.
 
−
* Jelsoft Enterprises Ltd. (2005). [http://www.cyclingforum.org/forums/ CyclingForum.org]. Retrieved March 30, 2005.
 
 
* Jones, David E. H. (1970). [http://ist-socrates.berkeley.edu/~fajans/Teaching/MoreBikeFiles/JonesBikeBW.pdf The Stability of the Bicycle]. Scanned in copy for download for personal use.
 
* Jones, David E. H. (1970). [http://ist-socrates.berkeley.edu/~fajans/Teaching/MoreBikeFiles/JonesBikeBW.pdf The Stability of the Bicycle]. Scanned in copy for download for personal use.
−
* Killian, Michael (2004). [http://www.sidewaysbike.com/ SidewaysBike (Not Your Father's Bicycle)] Retrieved March 30, 2005.
 
−
* Lessing, Hans-Erhard (1997). [http://www.cyclepublishing.com/history/leonardo%20da%20vinci%20bicycle.html The Leonardo da Vinci Bicycle Hoax]. Cycle Publishing. Retrieved March 30, 2005.
 
−
* Townsend, Andy (2005). [http://www.rider-ed.com/tips/motorcyclestability.htm  Motorcycle Stability and Steering]. Rider Education of New Jersey, Inc. Retrieved March 30, 2005.
 
−
* Transportation Alternatives (2005). [http://www.transalt.org/blueprint/chapter15/index.html The advocates for cycling, walking, and environmentally sensible transportation] Retrieved March 30, 2005.
 
−
* Wachtel, Alan; Lewiston, Diana (2000). [http://www.bicyclinglife.com/Library/riskfactors.htm Risk Factors for Bicycle-Motor Vehicle Collisions at Intersections]. Bicycling Life Website. Retrieved March 30, 2005.
 
  
−
[[Category:Consumer goods]]
+
 
 
[[Category:Cycling]]
 
[[Category:Cycling]]
 
[[Category:Cycle types]]
 
[[Category:Cycle types]]
−
[[Category:Human powered vehicles]]
 
−
[[Category:National Toy Hall of Fame]]
 

Latest revision as of 08:32, 25 September 2009

This racing bicycle is built using lightweight, shaped aluminium tubing and carbon fiber stays and forks. It sports a drop handlebar and thin tires and wheels for efficiency and aerodynamics.
This mountain bicycle features oversized tires, a sturdy frame, front shock absorbers, and handlebars oriented perpendicular to the bike's axis


A bicycle, or bike, is a pedal-driven human-powered vehicle with two wheels attached to a frame, one behind the other. First introduced in 19th-century Europe, bicycles evolved quickly into their familiar, current design. Numbering over a billion worldwide. Bicycles provide the principal means of transportation in many regions, are a popular form of recreation, and have been adapted for use in many other fields of human activity, including children's toys, adult fitness, military and local police applications, courier services, and cycle sports.

The basic shape and configuration of the bicycle's frame, wheels, pedals, saddle, and handlebars have hardly changed since the first chain-driven model was developed around 1885, although many important details have since been improved, especially since the advent of modern materials and computer-aided design. These have allowed for a proliferation of specialized designs for individuals who pursue a particular type of cycling.

The bicycle has affected history considerably, in both the cultural and industrial realms. In its early years, bicycle construction drew on pre-existing technologies; more recently, bicycle technology has, in turn, contributed ideas in both old and newer areas.

History

Main article History of the bicycle

Several inventors and innovators contributed to the development of the bicycle. Its earliest known forebears were called velocipedes, and included many types of human-powered vehicles. One of these, the scooter-like dandy horse of the French Comte de Sivrac, dating to 1790, was long cited as the earliest bicycle. Most bicycle historians now believe that these hobby-horses with no steering mechanism probably never existed, but were made up by Louis Baudry de Saunier, a 19th-century French bicycle historian.

A smartly dressed couple seated on an 1886 "quadricycle" for two

The ancestor of the bicycle was probably first created by a German Baron, Karl Drais, who invented and patented his machine in 1817. A number of these draisines still exist, including one at the Paleis het Loo museum in Apeldoorn, the Netherlands. These were pushbikes, powered by the action of the rider's feet pushing against the ground. Scottish blacksmith Kirkpatrick MacMillan refined this in 1839 by adding a mechanical crank drive to the rear wheel, thus creating the first true "bicycle" in the modern sense. His system employed a pair of treadle drives connected by rods to a rear wheel crank, rather like a steam locomotive's driveshaft. Although the design was copied by at least two other Scottish builders, it was overtaken in popularity and influence by an inferior one. In the 1850s and 1860s, Frenchmen Ernest Michaux and Pierre Lallement took bicycle design in a different direction, placing the pedals on an enlarged front wheel. Their creation, which came to be called the "Boneshaker", featured a heavy steel frame on which they mounted wooden wheels with iron tires. Lallement emigrated to America, where he recorded a patent on his bicycle in 1866 in New Haven, Connecticut. The Boneshaker was further refined by James Starley in the 1870s. He mounted the seat more squarely over the pedals so that the rider could push more firmly, and further enlarged the front wheel to increase the potential for speed. With tires of solid rubber, his machine became known as the ordinary. British cyclists likened the disparity in size of the two wheels to their coinage, nicknaming it the penny-farthing. The primitive bicycles of this generation were difficult to ride, and the high seat and poor weight distribution made for dangerous falls.

Bicycle in Victorian Plymouth, with a predecessor of the Starley diamond-frame

The subsequent dwarf ordinary addressed some of these faults by adding gearing, reducing the front wheel diameter, and setting the seat further back, with no loss of speed. Having to both pedal and steer via the front wheel remained a problem. Starley's nephew, J. K. Starley, J. H. Lawson, and Shergold solved this problem by introducing the chain and producing rear-wheel drive. These models were known as dwarf safeties, or safety bicycles, for their lower seat height and better weight distribution. Starley's 1885 Rover is usually described as the first recognizably modern bicycle. Soon, the seat tube was added, creating the double-triangle, diamond frame of the modern bike.

While the Starley design was much safer, the return to smaller wheels made for a bumpy ride. The next innovations increased comfort and ushered in the 1890s Golden Age of Bicycles. In 1888, Scotsman John Boyd Dunlop introduced the pneumatic tire, which soon became universal. Soon after, the rear freewheel was developed, enabling the rider to coast without the pedals spinning out of control. This refinement led to the 1898 invention of coaster brakes. Derailleur gears and hand-operated, cable-pull brakes were also developed during these years, but were only slowly adopted by casual riders. By the turn of the century, bicycling clubs flourished on both sides of the Atlantic, and touring and racing were soon extremely popular.

American bike from 1896. The frame is made of bamboo
A more-than-typical Amsterdam 'granny bike'

Successful early bicycle manufacturers included Englishman Frank Bowden and German builder Ignaz Schwinn. Bowden started the Raleigh company in Nottingham in the 1890s, and was soon producing some 30,000 bicycles a year. Schwinn emigrated to the United States, where he founded his similarly successful company in Chicago in 1895. Schwinn bicycles soon featured widened tires and spring-cushioned, padded seats, sacrificing a certain amount of efficiency for increased comfort. Facilitated by connections between European nations and their overseas colonies, European-style bicycles were soon available worldwide. By the mid-20th century, bicycles had become the primary means of transportation for millions of people around the globe.

In many western countries, the use of bicycles levelled off or declined as motorized transportation became affordable and car-centred policies led to an increasingly hostile environment for bicycles. In North America, bicycle sales declined markedly after 1905, to the point where, by the 1940s, they had largely been relegated to the role of children's toys. However, in other parts of the world, such as China, India, and European countries such as Germany, Denmark, and the Netherlands, the traditional utility bicycle remained a mainstay of transportation; its design changed only gradually to incorporate hand-operated brakes, with internal hub gears allowing up to seven speeds. In the Netherlands, such so-called 'granny bikes' have remained popular, and are again in production.

In North America, increasing consciousness of physical fitness and environmental preservation spawned a renaissance of bicycling in the late 1960s. Bicycle sales in the US boomed, largely in the form of the racing bicycles, long used in such events as the hugely popular Tour de France. Sales were also helped by a number of technical innovations that were new to the US market, including higher performance steel alloys and gearsets with an increasing number of gears. While 10-speeds were the rage in the 1970s, 12-speed designs were introduced in the 1980s, and today most bikes feature 18 or more speeds. By the 1980s, these newer designs had driven the three-speed bicycle from the roads. In the late 1980s, the mountain bike became particularly popular, and in the 1990s something of a major fad. These task-specific designs led many American recreational cyclists to demand a more comfortable and practical product. Manufacturers responded with the hybrid bicycle, which restored many of the features long enjoyed by riders of the time-tested European utility bikes.

Technical aspects

Reflectors for night riding are one of many available safety accessories

Legal requirements

The 1968 Vienna Convention on Road Traffic considers a bicycle to be a vehicle, and a person controlling a bicycle is considered a driver. The traffic codes of many countries reflect these definitions and demand that a bicycle satisfy certain legal requirements, sometimes even including licencing, before it can be used on public roads. In many jurisdictions it is an offense to use a bicycle that is not in roadworthy condition. In some places, bicycles must have functioning front and rear lights or lamps. As some generator or dynamo-driven lamps only operate while moving, rear reflectors are frequently also mandatory. Since a moving bicycle makes very little noise, in many countries bicycles must have a warning bell for use when approaching pedestrians, equestrians and other bicyclists.

Construction and parts

Frame

Template:Main

Nearly all modern upright bicycles feature the diamond frame, composed of two triangles: the front triangle and the rear triangle. The front triangle consists of the head tube, top tube, down tube and seat tube. The head tube contains the headset, the set of bearings that allows the fork to spin smoothly. The top tube connects the head tube to the seat tube at the top, and the down tube connects the head tube to the bottom bracket. The rear triangle consists of the seat tube and paired chain stays and seat stays. The chain stays run parallel to the chain, connecting the bottom bracket to the rear dropouts. The seat stays connect the top of the seat tube at or near the same point as the top tube) to the rear dropouts.

Historically, women's bicycle frames had a top tube that connected in the middle of the seat tube instead of the top, resulting in a lower standover height. This allowed the rider to dismount while wearing a skirt or dress. Although some women's bicycles continue to use this frame style, there is also a hybrid form, the mixte or step-through frame, which also allows easier mounting and dismounting for both male and female riders.

Historically, materials used in bicycles have followed a similar pattern as in aircraft, the goal being strength and low weight. Since the late 1930s alloy steels have been used for frame and fork tubes in higher quality machines. Celluloid found application in mudguards, and aluminium alloys are increasingly used in components such as handlebars, seat post, and brake levers. In the 1980s aluminium alloy frames became popular, and their affordability now makes them common. More expensive carbon fiber and titanium frames are now also available, as well as advanced steel alloys.

Drivetrain

Template:Details

The drivetrain begins with pedals which rotate the crankset, which fit into the bottom bracket. Attached to the crank is the chainring or sprocket which drives the chain, which in turn rotates the rear wheel via the rear sprockets, or cassette. Various gearing systems, described below, may be interspersed between the pedals and rear wheel; these gearing systems vary the number of rear wheel revolutions produced by each turn of the pedals.

Since cyclists' legs produce a limited amount of power most efficiently over a narrow range of cadences, a variable gear ratio is needed to maintain an optimum pedaling speed while covering varied terrain. The gear systems are usually hand-operated, via cables (or rarely, hydraulics), and are of two types.

  • Internal hub gearing works by planetary, or epicyclic, gearing, in which the outer case of the hub gear unit turns at a different speed relative to the rear axle depending on which gear is selected. Rear hub gears may offer 3, 4, 5, 6, 7, 8, 12, or 14 speeds. Bottom bracket fittings offer a choice of 2 speeds, and are generally foot-operated.
  • External gearing utilizes derailleurs, which can be placed on both the front chainring and on the rear cluster or cassette, to push the chain to either side, derailing it from the sprockets. The sides of the gear rings catch the chain, pulling it up onto their teeth to change gears. There may be 1 to 3 chainrings, and 5 to 10 sprockets on the cassette.

Internal hub gears are much less affected by adverse weather conditions than derailleurs, and often last longer and require less maintenance. However, they may be heavier and/or more expensive, and often do not offer the same range or number of gears. Internal hub gearing still predominates in some regions, particularly on utility bikes, whereas in other regions, such as the USA, external derailleur systems predominate.

Road bicycles have close set multi-step gearing, which allows very fine control of cadence, while utility cycles offer fewer, more widely spaced speeds. Mountain bikes and most entry-level road racing bikes may offer an extremely low gear to facilitate climbing slowly on steep hills.

Fixed-gear track racing bikes have transmission efficiencies of over 99% (nearly all the energy put in at the pedals ends up at the wheel). While generally variable ratio gear mechanisms are essential for human efficiency, they do reduce mechanical efficiency. The efficiency varies considerably with the gear ratio being used. In a typical hub gear mechanism the mechanical efficiency will be between 82% and 92% depending on the ratio selected. Which ratios are best and worst depends on the specific model of hub gear. Derailleur type mechanisms fare better, with a typical mid-range product (of the sort used by serious amateurs) achieving between 88% and 99% efficiency at 100W. In derailleur mechanisms the highest efficiency is achieved by the larger cogs. Efficiency generally decreases with smaller cog sizes because the chain must bend more sharply as it rolls on and off the cog, and it also forms a sharp angle at the chain tensioner. See Chapter 9 of "Bicycling Science" (Reference, below) for details of transmission efficiency.</ref> Derailleur efficiency is also compromised with cross-chaining, or running large-ring to large-cog or small-ring to small-cog. This also results in increased wear because of the lateral deflection of the chain. Retro-Direct drivetrains used on some early 20th century bicycles have been resurrected by bicycle hobbyists.

Some early 20th C. bicycles dispensed with the chain entirely and used an enclosed driveshaft and bevel gears. These were strongly built but were not mechanically efficient. They were primarily marketed to women as the enclosed gears would not entangle clothing.

Steering and seating

The handlebars rotate the fork and the front wheel via the stem, which articulates with the headset. Three styles of handlebar are common. Touring handlebars, the norm in Europe and elsewhere until the 1970s, curve gently back toward the rider, offering a natural grip and comfortable upright position. Racing handlebars are "dropped", offering the cyclist either an aerodynamic "hunched" position or a more upright posture in which the hands grip the brake lever mounts. Mountain bikes feature a crosswise handlebar, which helps prevent the rider from pitching over the front in case of sudden deceleration.

Variations on these styles exist. Bullhorn style handlebars are often seen on modern time trial bicycles, equipped with two forward-facing extensions, allowing a rider to rest his entire forearm on the bar. These are usually used in conjunction with the aero bar, a pair of forward-facing extensions spaced close together, to promote better aerodynamics. The Bullhhorn was banned from ordinary road racing because it is difficult for the rider to control in bike traffic.

Seats, or saddles, also vary with rider preference, from the cushioned ones favoured by short-distance riders to narrower seats which allow more free leg swings. Comfort depends on riding position. With comfort bikes and hybrids the cyclist sits high over the seat, their weight directed down onto the saddle, such that a wider and more cushioned saddle is preferable. For racing bikes where the rider is bent over, weight is more evenly distributed between the handlebars and saddle, and the hips are flexed, and a narrower and harder saddle is more efficient.

Recumbent bicycles have more chair-like seats, and so are much more comfortable to ride, although generally slower up hills due to this positioning. The reclined, low seating position does provide increased aerodynamics over standard seating.

Brakes

Template:Main

Modern bicycle brakes are either rim brakes, in which friction pads are compressed against the wheel rims, internal hub brakes, in which the friction pads are contained within the wheel hubs, or disc brakes. A rear hub brake may be either hand-operated or pedal-actuated, as in the back pedal coaster brakes which were the rule in North America until the 1960s. Hub drum brakes do not cope well with extended braking, so rim brakes are favoured in hilly terrain. With hand-operated brakes, force is applied to brake handles mounted on the handle bars and then transmitted via Bowden cables to the friction pads. In the late 1990s, disc brakes appeared on some off-road bicycles, tandems and recumbent bicycles, but are considered impractical on road bicycles, which rarely encounter conditions where the advantages of discs are significant.

The advantages of discs make them well-suited to steep, extended downhills through wet and muddy off-road terrain, which falls under the category of downhill and freeride bicycle riding. The use of tires as large as 3.0 inches in width also makes disc brakes a necessity, as rim brakes simply cannot straddle a tire that wide.

Two main disc brake systems exist: hydraulic and mechanical (cable-actuated). Mechanical disc brakes have less modulation than hydraulic disc brake systems, and since the cable is usually open to the outside, mechanical disc brakes tend to pick up small bits of dirt and grit in the cable lines when ridden in harsh terrain. Hydraulic disc brake systems generally keep contaminants out better. However, since hydraulic disc brakes usually require relatively specialized tools to bleed the brake systems, repairs on the trail are difficult to perform, whereas mechanical disc brakes rarely fail. Also, the hydraulic fluid may boil on steep, continuous downhills. This is due to heat building up in the disc and pads and can cause the brake to lose its ability to transmit force through incompressible fluids, since some of it has become a gas, which is compressible. To avoid this problem, 203 mm (8 inch) diameter disc rotors have become common on downhill bikes. Larger rotors dissipate heat more quickly and have a larger amount of mass to absorb heat. For these reasons, one must weigh the advantages and disadvantages of using a hydraulic system versus a mechanical system.

For track cycling, track bicycles do not have brakes. Most track bike frames and forks do not have holes for mounting brakes, although with their increasing popularity among some road cyclists, some manufacturers have drilled their track frames to enable the fitting of brakes. Brakes are not required for riding on a track because all riders ride in the same direction and there are no corners or other traffic. Track rider are still able to slow down because all track bicycles are fixed, meaning that there is no freewheel. Without a freewheel, coasting is impossible, so when the rear wheel is moving, the crank is moving. To slow down one may apply resistance to the pedals. Cyclists who ride a track bike without brake(s) on the road can also slow down by skidding, by unweighting the rear wheel and applying a backwards force to the pedals, causing the rear wheel to lock up and slide along the road.

Accessories and repairs

Utility bicycles have many standard features which enhance their usefulness and comfort that would be considered accessories on sports bicycles. Chainguards and mudguards, or fenders, protect clothes and moving parts from oil and spray. Kick stands help with parking. Front-mounted wicker or steel baskets for carrying goods are often used. Rear racks or carriers can be used to carry items such as school satchels. Parents sometimes add rear-mounted child seats and/or an auxiliary saddle fitted to the crossbar to transport children.

Touring bicycle equipped with head lamp, pump, rear rack, fenders/mud-guards, and numerous saddle-bags.

Other accessories include lights, pump, lock, and additional (pedal or wheel-mounted) reflectors. Technical accessories include solid-state speedometers and odometers for measuring distance. Toe-clips and toestraps help to keep the foot planted firmly on the pedals, and enable the cyclist to pull as well as push the pedals.

In most countries where cycling is common, bicycle helmet use is negligible. In North America a significant minority, possibly up to 25% of bicyclists, wear helmets. While no U.S. federal law requires helmets, many states require children to wear them, and some municipalities require them for all riders. In Australia and New Zealand, and parts of Canada, helmets are required by law. Outside the West, use of helmets by utility cyclists is practically unknown. No correlation between decreased injury rates and helmet use has been demonstrated in whole populations.

Many cyclists carry tool kits, containing at least a tire patch kit (and/or a spare tube), tire levers, and allen wrenches. A single tool once sufficed for most repairs. More specialised parts now require more complex tools, including proprietary tools specific for a given manufacturer. Some bicycle parts, particularly hub-based gearing systems, are complex, and many prefer to leave maintenance and repairs to professionals. Others maintain their own bicycles, enhancing their enjoyment of the hobby of cycling.

Performance

In both biological and mechanical terms, the bicycle is extraordinarily efficient. In terms of the amount of energy a person must expend to travel a given distance, investigators have calculated it to be the most efficient self-powered means of transportation. From a mechanical viewpoint, up to 99% of the energy delivered by the rider into the pedals is transmitted to the wheels, although the use of gearing mechanisms may reduce this by 10-15%. In terms of the ratio of cargo weight a bicycle can carry to total weight, it is also a most efficient means of cargo transportation.

A human being travelling on a bicycle at low to medium speeds of around 10-15 mph (16-24 km/h), using only the energy required to walk, is the most energy-efficient means of transport generally available. Air drag, which increases with the square of speed, requires increasingly higher power outputs relative to speed. A bicycle in which the rider lies in a prone position and which may be covered in an aerodynamic fairing to achieve very low air drag is referred to as a Recumbent bicycle or Human Powered Vehicle.

For more detail, see bicycle performance

Balance

Template:Main

A bicycle stays upright when it is steered to keep its center of gravity over its wheels. Lock the steering of a bicycle and it is virtually impossible to ride. Cancel the gyroscopic effect of rotating bicycle wheels by adding counter-rotating wheels, and it can still be easily ridden.

Further reading

For more information on the technical aspects of bicycles, see also:

Social and historical aspects

Present day: Bikes still popular in Amsterdam

Economic implications

Bicycle manufacturing proved to be a training ground for other industries. Building modern bicycle frames led to the development of advanced metalworking techniques, both for the frames themselves and for special components such as ball bearings, washers, and sprockets. These techniques later enabled skilled metalworkers and mechanics to develop the components used in early automobiles and aircraft. J. K. Starley's company became the Rover Cycle Company Ltd. in the late 1890s, and then the Rover auto maker. The Morris Motor Company (in Oxford) and Škoda also began in the bicycle business, as did Henry Ford and the Wright Brothers.

Some bicycle clubs and national associations became prominent advocates for improvements to roads and highways. In the United States, the League of American Wheelmen lobbied for the improvement of roads in the last part of the 19th century, founding and leading the national Good Roads Movement. Both their model for political organization and the paved roads for which they argued facilitated the growth of the bicycle's rival, the automobile.

In recent years, US and European bicycle makers have moved much of their production to Asia. Some sixty percent of the world's bicycles are now being made in China. Despite this shift in production, as nations such as China and India become more wealthy, their own use of bicycles has declined. One of the major reasons for the proliferation of Chinese-made bicycles in foreign markets is the increasing affordability of cars and motorcycles for its own citizens.

Female emancipation

Woman with bicycle, 1890s

The diamond-frame safety bicycle gave women unprecedented mobility, contributing to their emancipation in Western nations. As bicycles became safer and cheaper, more women had access to the personal freedom they embodied, and so the bicycle came to symbolise the New Woman of the late nineteenth century, especially in Britain and the United States.

The bicycle was recognised by nineteenth-century feminists and suffragists as a "freedom machine" for women. American Susan B. Anthony said: "Let me tell you what I think of bicycling. I think it has done more to emancipate women than anything else in the world. It gives women a feeling of freedom and self-reliance. I stand and rejoice every time I see a woman ride by on a wheel...the picture of free, untrammeled womanhood." In 1895 Frances Willard, the tightly-laced president of the Women’s Christian Temperance Union, wrote a book called How I Learned to Ride the Bicycle, in which she praised the bicycle she learned to ride late in life, and which she named "Gladys", for its "gladdening effect" on her health and political optimism. Willard used a cycling metaphor to urge other suffragists to action, proclaiming, "I would not waste my life in friction when it could be turned into momentum."

The male anger at the freedom symbolised by the New (bicycling) Woman was demonstrated when the male undergraduates of Cambridge University chose to show their opposition to the admission of women as full members of the university by hanging a woman in effigy in the main town square -- tellingly, a woman on a bicycle. This was as late as 1897.[1]

In the 1890s the bicycle craze led to a movement for so-called rational dress, which helped liberate women from corsets and ankle-length skirts and other restrictive garments, substituting the then-shocking bloomers.

Other social implications

Sociologists suggest that bicycles enlarged the gene pool for rural workers, by enabling them to easily reach the next town and increase their courting radius. In cities, bicycles helped reduce crowding in inner-city tenements by allowing workers to commute from more spacious dwellings in the suburbs. They also reduced dependence on horses, with all the knock-on effects this brought to society. Bicycles allowed people to travel for leisure into the country, since bicycles were three times as energy efficient as walking, and three to four times as fast.

Uses for bicycles

Bicycles at work

Police officer on a bicycle

The postal services of many countries have long relied on bicycles. The British Royal Mail first started using bicycles in 1880; now bicycle delivery fleets include 37,000 in the UK, 25,700 in Germany and 10,500 in Hungary. The London Ambulance Service has recently introduced bicycling paramedics, who can often get to the scene of an incident in Central London more quickly than a motorised ambulance.

Police officers adopted the bicycle as well, initially using their own. However, they eventually became a standard issue, particularly for police in rural areas. The Kent police purchased 20 bicycles in 1896, and by 1904 there were 129 police bicycle patrols operating. Some countries retained the police bicycle while others dispensed with them for a time. Bicycle patrols are now enjoying a resurgence in many cities, as the mobility of car-borne officers is becoming increasingly limited by traffic congestion and pedestrianisation. They also have the advantages that the officers are inherently more open to the public, and the transport is quieter to permit a more stealthy approach toward suspects. The pursuit of suspects can also be assisted by a bicycle.

A bicycle loaded with tender coconut for sale. Karnataka, India

Bicycles enjoy substantial use as general delivery vehicles in many countries. In the UK and North America, generations of teenagers have got their first jobs delivering newspapers by bicycle. London has many delivery companies that use bicycles with trailers. Most cities in the West, and many outside it, support a sizable and visible industry of cycle couriers who deliver documents and small packages. In India, many of Mumbai's Dabbawalas use bicycles to deliver hot lunches to the city’s workers. In Bogotá, Colombia the city’s largest bakery recently replaced most of its delivery trucks with bicycles. Even the car industry uses bicycles. At the huge Mercedes-Benz factory in Sindelfingen, Germany workers use bicycles, colour-coded by department, to move around the factory.

Bicycle recreation

File:WhiteBikesVeluwe.jpg
In the Netherlands, bicycles are made available for use in national parks

Bicycles are used for recreation at all ages. Bicycle touring, also known as cyclotourism, involves touring and exploration or sightseeing by bicycle for leisure. A brevet or randonnée is an organized long-distance ride.

One aspect of Dutch popular culture is enjoying relaxed cycling in the countryside of the Netherlands. The land is very flat and full of public bicycle trails where cyclist aren't bothered by cars and other traffic, which makes it ideal for cycling recreation. Many Dutch people subscribe every year to an event called fietsvierdaagse — four days of organised cycling through the local environment. Paris-Brest-Paris (PBP), which began in 1891, is the oldest bicycling event still run on a regular basis on the open road, covers over 1200 km and imposes a 90-hour time limit.

Bicycles and war

Template:Main

The bicycle is not suited for combat, but it has been used as a method of transporting soldiers and supplies to combat zones. Bicycles were used in the Second Boer War, where both sides used them for scouting. In World War I, France and Germany used bicycles to move troops. In its 1937 invasion of China, Japan employed some 50,000 bicycle troops, and similar forces were instrumental in Japan's march through Malaya in World War II. Germany used bicycles again in World War II, while the British employed airborne Cycle-commandos with folding bikes.

In the Vietnam War, communist forces used bicycles extensively as cargo carriers along the Ho Chi Minh Trail. There are reports of mountain bicycles being used in scouting by U.S. Special Forces in the U.S. invasion of Afghanistan and in subsequent battles against the Taliban. The only country to recently maintain a regiment of bicycle troops was Switzerland, who disbanded the last unit in 2003.

Bicycle racing

Template:Main

Shortly after the introduction of bicycles, competitions developed independently in many parts of the world. Early races involving boneshaker style bicycles were predictably fraught with injuries. Large races became popular during the 1890's "Golden Age of Cycling", with events across Europe, and in the U.S. and Japan as well. At one point, almost every major city in the US had a velodrome or two for track racing events. However since the middle of the 20th Century cycling has become a minority sport in the US whilst in Continental Europe it continues to be a major sport, particularly in France, Belgium and Italy. The most famous of all bicycle races is the Tour de France. This began in 1903, and continues to capture the attention of the sporting world.

As the bicycle evolved its various forms, different racing formats developed. Road races may involve both team and individual competition, and are contested in various ways. They range from the one-day road race, criterium, and time trial to multi-stage events like the Tour de France and its sister events which make up cycling's Grand Tours. Recumbent bicycles were banned from bike races in 1934 after Marcel Berthet set a new hour record in his Velodyne streamliner (49.992 km on Nov 18, 1933). Track bicycles are used for track racing in Velodromes , while cyclo-cross races are held on rugged outdoor terrain. In the past decade, mountain bike racing has also reached international popularity and is even an Olympic sport.

The governing body of international cycle sport, the Union Cycliste Internationale, decided in the late 1990s to create additional rules restricting the design of racing bicycles. These rules met with considerable controversy and to some extent arrested the development of the racing bicycle. Their stated motive was so that developing countries could compete in international competitions without requiring large equipment budgets, and to re-focus attention on the athlete rather than the bicyle. For example, monocoque frames, such as used by Chris Boardman to win the Gold medal in 1992 Olympic individual pursuit event in Barcelona, were no longer permitted.

Modal share: cycle use in modern cities

Template:Main

Cyclists and motorists make different demands on road design which may lead to conflicts both in politics and on the streets. Some jurisdictions give priority to motorised traffic, for example setting up extensive one-way street systems, free-right turns, high capacity roundabouts, and slip roads. Other cities may apply active traffic restraint measures to limit the impact of motorised transport. In the former cases, cycling has tended to decline while in the latter it has tended to be maintained. Occasionally, extreme measures against cycling may occur. In Shanghai, a city where bicycles were once the dominant mode of transportation, bicycle travel on city roads was actually banned temporarily in December 2003.

In areas in which cycling is popular and encouraged, cycle-parking facilities using bicycle racks, lockable mini-garages, and patrolled cycle parks are used to reduce theft. Local governments also promote cycling by permitting the carriage of bicycles on public transport or by providing external attachment devices on public transport vehicles. Conversely, an absence of secure cycle-parking is a recurring complaint by cyclists from cities with low modal share of cycling.

Extensive bicycle path systems may be found in some cities. Such dedicated paths often have to be shared with inline skaters, scooters, skateboarders, and pedestrians. Segregating bicycle and automobile traffic in cities has met with mixed success, both in terms of safety and bicycle promotion. At some point the two streams of traffic inevitably intersect, often in a haphazard and congested fashion. Studies have demonstrated that, due to the high incidence of accidents at these sites, such segregated schemes can actually increase the number of car-bike collisions.


Cycling activism

Cyclists form associations, both for specific interests (trails development, road maintenance, urban design, racing clubs, touring clubs, etc.) and for more global goals (energy conservation, pollution reduction, promotion of fitness). Two broad themes run in bicycle activism: one more overtly political with roots in the environmental movement; the other drawing on the traditions of the established bicycle lobby.

Such groups promote the bicycle as an alternative mode of transport and emphasize the potential for energy and resource conservation and health benefits gained from cycling versus automobile use. Activists in both camps also argue for improved local and inter-city rail services and other methods of mass transportation, and also for greater provision for cycle carriage on such services. Many cities also have community bicycle programs that promote cycling, especially as a means of inner-city transport.

San Francisco Critical Mass, 29th April, 2005.

Controversially, some bicycle activists (including some traffic management advisors) seek the construction of segregated cycle facilities for journeys of all lengths. Other activists, especially those from the more established tradition, view the safety, practicality, and intent of many segregated cycle facilities with suspicion. They favour a more holistic approach based on the 4 'E's; education (of everyone involved), encouragement (to apply the education), enforcement (to protect the rights of others), and engineering (to facilitate travel while respecting every person's equal right to do so). In some cases this opposition has a more ideological basis: some members of the Vehicular Cycling movement oppose segregated public facilities, such as on-street bike lanes, on principle. Some groups offer training courses to help cyclists integrate themselves with other traffic. This is part of the ongoing cycle path debate.

Critical Mass is a worldwide activist movement of mass bicycle protest rides. It incorporates the themes of increasing the road- and mind-share given to bicycle transport, and has drawn support from environmentally minded campaigners and other schools of political thought. According to participants in Critical Mass, "We aren't blocking traffic, we are traffic!" However, their particular forms of protest has drawn criticism from the broader streams of activism.

There is a long-running cycle helmet debate among activists. The most heated controversy surrounds the topic of compulsory helmet use.

Types of bicycle

There are many different types of bicycle. See also Category:Cycle types.

By function

Utility bicycles parked outside an academic building at Stanford University
  • Utility bicycles are designed for commuting, shopping and running errands. They employ middle or heavy weight frames and tires, internal hub gearing, and a variety of helpful accessories. The riding position is usually upright.
  • Mountain bicycles are designed for off-road cycling, and include other sub-types of off-road bicycles such as Cross Country (i.e."XC"), Downhill , and to a lesser extent Freeride bicycles. All mountain bicycles feature sturdy, highly durable frames and wheels, wide-gauge treaded tires, and cross-wise handlebars to help the rider resist sudden jolts. Some mountain bicycles feature various types of suspension systems (e.g. coiled spring, air or gas shock), and hydraulic or mechanical disc brakes. Mountain bicycle gearing is very wide-ranging, from very low ratios to high ratios, typicaly with 21 to 30 gears.
  • Racing bicycles are designed for speed, and include road, time trial, and track bicycles. They have lightweight frames and components with minimal accessories, dropped handlebars to allow for an aerodynamic riding position, narrow high-pressure tires for minimal rolling resistance and multiple gears. Racing bicycles have a relatively narrow gear range, and typically varies from medium to very high ratios, distributed across 18, 20, 27 or 30 gears. The more closely spaced gear ratios allow racers to choose a gear which will enable them to ride at their optimun pedaling cadence for maximum efficency.
    • Time trial bicycles are similar to road bicycles but are differentiated by a more aggressive frame geometry that throws the rider into a more compact (i.e "aero") riding position. They also feature aerodynamic frames, wheels, and handlebars.
    • Track bicycles, intended for indoor or outdoor cycle tracks or velodromes, are exceptionally simple compared with road bikes. They have a single gear ratio, a fixed drivetrain (i.e. no freewheel), no brakes, and are minimally adorned with other components that would otherwise be typical for a racing bicycle.
  • Messenger bikes are typically used for urgent deliveries of letters and small packages between businesses in big cities with heavily congested traffic. While any bike can be used, messenger bikes often resemble track bicycles (especially in the USA).
A modern touring bicycle, with accessories and baggage
  • Touring bicycles are designed for bicycle touring and long journeys. They are durable and comfortable, capable of transporting baggage, and may feature any type of gearing system.
  • Randonneur or Audax bicycles are designed for randonnées or brevet rides, and fall in between racing bicycles and those intended for touring.
  • Recumbent bicycles, which are sometimes referred to as Bents in the USA, are designed to maximise comfort and minimise wind resistance. Whereas most of the other types of bicycle in this section are designed around a ‘diamond frame’ geometary, where the pedals and chainset are located at the bottom of the bicycle and handlebars are at the front, recumbent bicycles (recumbents) generally use a “boom” and rear triangle combination with the pedals and chainset located at the front of the boom and the handlebars are located either “over seat” or “underseat” in the centre.

By number of riders

  • A tandem or twin has two riders.
  • A triplet has three riders; a quadruplet has four.
  • The largest multi-bike had 40 riders.[2]

In most of these types the riders ride one behind the other. Exceptions are "The Companion", or "sociable," a side-by-side two-person bike (that converted to a single-rider) built by the Punnett Cycle Mfg. Co. in Rochester, N. Y. in the 1890s. Another bicycle, the "Conference Bike", rented to tourists in Berlin carries seven people seated in a circle.

By general construction

  • A penny-farthing or ordinary has one high wheel directly driven by the pedals and one small wheel.
  • On an upright bicycle the rider sits astride the saddle. This is the most common type.
  • On a recumbent bicycle the rider reclines or lies supine.
  • A Pedersen bicycle has a bridge truss frame.
  • A folding bicycle can be quickly folded for easy carrying, for example on public transport.
  • A Moulton Bicycle has a traditional seating position, and utilises small diameter, high pressure tires and front and rear suspension.
  • An exercise bicycle remains stationary; it is used for exercise rather than propulsion.

By gearing

  • Internal hub gearing is most common in European utility bicycles, usually ranging from three-speed bicycles to five and seven speed options. But hub gears with eight and fourteen speeds are available as well.
  • Shaft-driven bicycles use a driveshaft rather than a chain to power the rear wheel. These are often used as commuter bikes because they eliminate inconveniences associated with chains and pant-legs, but they are less efficient than chain-driven bicycles. Shaft- driven bicycles usually employ internal hub gearing.
  • Derailleur gears, featured on most racing and touring bicycles, offering from 5 to 30 speeds
  • Single-speed bicycles and Fixed-gear bicycles have only one gear, and include all BMX bikes, children's bikes, crowded city messenger bikes, and many others. The fixed gear has no freewheel mechanism, so whenever the bike is in motion the pedals continue to spin. An advantage of this is the pedals can also be used to slow down.
  • Retro-Direct bicycles have two sprockets on the rear wheel. By backpedaling, the secondary, usually lower, gear is engaged.
Flatland rider on a BMX bike

By sport

  • Track bicycles are ultra-simple, lightweight fixed-gear bikes with no brakes, designed for track cycling on purpose-built cycle tracks, often in velodromes.
  • Time trial bicycles are similar to road bicycles with an extremely aerodynamic design for use in a cycling time trial.
  • Cyclo-cross bicycles are lightweight enough to be carried over obstacles, and robust enough to be cycled through mud.
  • Down-hill racers are a specialized type of mountain bike with a very strong frame, altered geometry, and long travel suspension. They are designed for use only on downhill tracks.
  • BMX (bicycle motocross) bicycles have small wheels and are used for BMX racing, as well as freestyle with tricks such as wheelies. Freestyle BMXers often ride dirt jumps and skatepark ramps.
  • Triathlon bicycles have seat posts that are closer to vertical than the seat posts on road racing bicycles. This concentrates the effort of cycling in the quadriceps muscles, sparing the other large muscles of the leg for the running segment of the race. Triathlon bicycles also have specialized handlebars known as triathlon bars or aero bars.

By means of propulsion

  • A pedal cycle is driven by pedals.
  • A hand-cranked bicycle is driven by a hand crank.
  • A rowing bicycle is driven by a rowing action using both arms and legs.
  • A Motorized bicycle provides motor assistance.
  • A moped propels the rider with a motor, but includes bicycle pedals for human propulsion.
  • a "Flywheel" uses stored kinetic energy.

Other types

  • Hybrid bicycles are a compromise between the mountain and racing style bicycles which replaced European-style utility bikes in North America in the early 1990s. They have a light frame, medium gauge wheels, and derailleur gearing, and feature straight or curved-back, touring handlebars for more upright riding.
  • Cruiser bicycles are designed for comfort, with curved back handlebars, padded seats, and balloon tires. Cruisers typically have minimal gearing and are often available for rental at beaches and parks which feature flat terrain.
  • Freight bicycles are designed for transporting large or heavy loads.
  • Cycle rickshaws (also called pedicabs or trishaws) are used to transport passengers for hire.
  • Velomobiles or bicycle cars provide enclosed pedal-powered transportation.
  • Clown bicycles are designed for comedic effect or stunt riding. Some types of clown bicycles are:
    • bucking bike (with one or more eccentric wheels)
    • tall bike (often called an upside down bike, constructed so that the pedals, seat and handlebars are all higher than normal) -- other types of tall bikes are made by welding two or more bicycle frames on top of each other, and running additional chains from the pedals to the rear wheel.
    • Come-apart bike, (essentially a unicycle, plus a set of handlebars attached to forks and a wheel).
Clown bikes are also built that are directly geared, with no freewheeling, so that they may be pedaled backwards. Some are built very small but are otherwise normal.
  • Art bikes: Some bikes are built so that the frame appears to be made of junk or found objects: Bongo the Clown built several ridable parade bikes which were as much kinetic sculptures as transport.
  • A unicycle is not a bicycle, as it has only one wheel, but it is related.

Standards

A number of formal and industry standards exist for bicycle components, to help make spare parts exchangeable:

  • ISO 5775 Bicycle tire and rim designations
  • ISO 8090 Cycles — Terminology (same as BS 6102-4)
  • ISO 4210 Cycles — Safety requirements for bicycles

See also

Bicycles in the snow


References

  • All About Bicycling, Rand McNally.
  • Richard Ballantine, Richard's Bicycle Book, Pan, 1975.
  • Caunter C. F. The History and Development of Cycles Science Museum London 1972.
  • Daniel Kirshner. Some nonexplanations of bicycle stability. American Journal of Physics, 48(1), 1980. The abstract reads "In this paper we attempt to verify a nongyroscopic theory of bicycle stability, and fail".
  • David B. Perry, Bike Cult: the Ultimate Guide to Human-powered Vehicles, Four Walls Eight Windows, 1995.
  • Roni Sarig, The Everything Bicycle Book, Adams Media Corporation, 1997
  • US Department of Transportation, Federal Highway Administration. "America's Highways 1776-1976", pp. 42-43. Washington, DC, US Government Printing Office.
  • David Gordon Wilson, Bicycling Science, MIT press, ISBN 0-262-73154-1
  • David V. Herlihy, Bicycle: The History, Yale University Press, 2004
  • Frank Berto, The Dancing Chain: History and Development of the Derailleur Bicycle, San Francisco: Van der Plas Publications, 2005, ISBN 1-892495-41-4.
  • The Data Book: 100 Years of Bicycle Component and Accessory Design, San Francisco: Van der Plas Publications, 2005, ISBN 1-892495-01-5.

External links

Retrieved from "http://woiweb.com/wiki/index.php?title=Bicycle&oldid=60147"