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Bicycle
A bicycle, also known as a bike, push bike or cycle, is a pedal-driven, human-powered vehicle with two wheels attached to a frame, one behind the other. A person who rides a bicycle is called a cyclist or a bicyclist.
Bicycles were introduced in the 19th century and now number about one billion worldwide, twice as many as automobiles.[1] They are the principal means of transportation inmany regions. They also provide a popular form of recreation, and have been adapted for such uses as children's toys, adult fitness, military and police applications, courier services, and competitive sports.
The basic shape and configuration of a typical bicycle has changed little since the first chain-driven model was developed around 1885.[2] Many details have been improved, especially sincethe advent of modern materials and computer-aided design. These have allowed for a proliferation of specialized designs for particular types of cycling.
The invention of the bicycle has had an enormous impact on society, both in terms of culture and of advancing modern industrial methods. Several components that eventually played a key role in the development of the automobile were originallyinvented for the bicycle – e.g., ball bearings, pneumatic tires, chain-driven sprockets, spoke-tensioned wheels, etc.
Contents[hide] * 1 History * 2 Uses * 3 Technical aspects * 3.1 Types * 3.2 Dynamics * 3.3 Performance * 3.4 Construction and parts * 3.4.1 Frame * 3.4.2 Drivetrain and gearing * 3.4.3 Steering and seating * 3.4.4Brakes * 3.4.5 Suspension * 3.4.6 Wheels * 3.4.7 Accessories, repairs, and tools * 3.4.8 Standards * 3.4.9 Parts * 4 Social and historical aspects * 4.1 In daily life * 4.2 Female emancipation * 4.3 Economic implications * 4.4 Legal requirements * 5 See also * 6 Notes * 7 References * 8 External links |
[edit]History
Main article: History of the bicycle

Wooden Dandy horse (around 1820), the first two-wheeler and as such the archetype of the bicycle
Multiple innovators contributed to the history of the bicycle by developing precursor human-powered vehicles. The documented ancestors of today's modern bicycle were known as draisines, hobby horses, or push bikes (and modern bicycles are sometimes stillcalled push bikes outside of North America). Being the first human means of transport to make use of the two-wheeler principle, the draisine (or Laufmaschine, "running machine"), invented by the German Baron Karl von Drais, is regarded as the forerunner of the modern bicycle. It was introduced by Drais to the public in Mannheim in summer 1817 and in Paris in 1818.[3] Its rider sat astride a woodenframe supported by two in-line wheels and pushed the vehicle along with his/her feet while steering the front wheel.

Michaux' son on velocipede 1868

Thomas McCall in 1869 on his velocipede
In the early 1860s, Frenchmen Pierre Michaux and Pierre Lallement took bicycle design in a new direction by adding a mechanical crank drive with pedals on an enlarged front wheel (the velocipede). AnotherFrench inventor by the name of Douglas Grasso had a failed prototype of Pierre Lallement's bicycle several years earlier. Several inventions followed using rear wheel drive , the best known being the rod-driven velocipede by Scotsman Thomas McCall in 1869. The French creation, made of iron and wood, developed into the "penny-farthing" (historically known as an "ordinary bicycle", a retronym,since there were then no other kind).[4] It featured a tubular steel frame on which were mounted wire spoked wheels with solid rubber tires. These bicycles were difficult to ride due to their very high seat and poor weight distribution.

A penny-farthing or ordinary bicycle photographed in the Škoda Auto museum in the Czech Republic

Bicycle in Plymouth, England at the start of the 20th century...