A motorcycle is a two-wheeled vehicle powered by an engine. The wheels are in-line, and at higher speed the motorcycle remains upright and stable by virtue of gyroscopic forces; at lower speeds continual readjustment of the steering by the rider gives stability. more...
The rider sits astride the vehicle on a seat, with hands on a set of handlebars which are used to steer the motorcycle, in conjunction with the rider shifting his weight through his feet, which are supported on a set of footpegs which stick out from the frame.
The inspiration for the earliest motorcycles, and arguably the first motorcycle, was designed and built by the German inventors Gottlieb Daimler and Wilhelm Maybach in Bad Cannstatt (a city district of Stuttgart) in 1885. It was the first petroleum-powered vehicle ever and, but for the provision of a pair of stabilizing wheels, a motorized bicycle, although they called their invention the Reitwagen ("riding car"). They had not set out to create a vehicle form but to build a simple carriage for the engine which was the focus of their endeavours. However,if one counts two wheels with steam propulsion as being a motorcycle, then the first one may have been American. One such machine was demonstrated at fairs and circuses in the eastern US in 1867, built by one Sylvester Howard Roper of Roxbury, Massachusetts. There is an existing example of a Roper machine, dated 1869. It's powered by a charcoal-fired two-cylinder engine, whose connecting rods directly drive a crank on the rear wheel. This machine predates the invention of the safety bicycle by many years, so its chassis is also based on the "bone-crusher" bike.
In 1894, the Hildebrand & Wolfmüller was the first motorcycle that was available for purchase.
In the early period of motorcycle history there were many manufacturers as producers of bicycles adapted their designs for the new internal combustion engine. As the engines became more powerful and designs outgrew the bicycle origins, the number of motorcycle producers reduced.
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