Bicycles were first developed in the mid-18th century and have long since been used as a form of transport. Originally, the front wheel was much larger than the rear wheel, and the rider was elevated a great deal, making them difficult to control and very dangerous. In 1885, J.K. Starley of England devised the more modern bike with a chain and gearing to allow the wheels to be of equal size. Although bicycle races had been held on the old "penny farthings", the new bikes stimulated the growth of bicycle racing as a sport.
从18世纪中期问世以来，自行车一直是一种广泛使用的交通工具。早期自行车的前轮比后轮大很多，而且车座也很高，使得骑车人很难控制车子。这种情况是相当危险的。1885年，英国的斯塔利（J.K. Starley）使用滚珠轴承及链条设计出了前、后车轮大小一样的现代自行车。虽然在此以前已经有使用老式4：1式自行车的（前轮尺寸是后轮的4倍）自行车赛，但现代自行车的出现刺激了自行车赛向竞技体育方面发展。 

Cycling at the Olympics features three exciting disciplines: road, track and mountain biking.
如今，奥运会自行车比赛分为公路赛、场地赛及山地赛三种。

About Cycling（Olympic sport since 1896）
自行车概述（1896年成为奥运会正式比赛项目）