自行车英文presentation.ppt

The bicycle you don’t know by 王道齐 德语122 Gear变速 brake刹车 suspension减震前叉 Frame车架 forks前叉 The history of bicycle Wooden?draisine?(around 1820), the first two-wheeler and as such the archetype of the bicycle The improve of bike The sort of bicycle Roadbicycle（公路车） Mountainbike（山地车） DownHillbike （速降自行车） Trackbicycle （场地自行车）（死飞） CyclingBMX （小轮车） Foldingbicycle （折叠车） Tandembicycle （多人自行车） Road bike Road bike geometry is designed to be efficient on road, so they may initially feel unusual compared to the upright position of commuter or mountain bikes. At the upper end of the market, bikes tend to either be very aerodynamic or very light, or a combination of the two logo Mountain bike Racing Touring Downhillbike Downhill?(DH)?bikes typically have eight or more inches (200?mm) of suspension travel. They are built with frames that are strong, yet light, which often requires the use of more expensive alloys and very recently, carbon fiber. trackbike Current events include:?time trial,?keirin,?individual pursuit,?team pursuit,?points race,?scratch race,?sprint,?team sprint,?omnium?and, for men only,madison. Womens events are shorter than mens. ?Most fixed-gear bicycles only have a front brake, and some have no brakes at all. * was invented by the German?Baron?Karl von Drais. It is regarded as the modern bicycles forerunner; Drais introduced it to the public in?Mannheim?in summer 1817 and in Paris in 1818.?Its rider sat astride a wooden frame supported by two in-line wheels and pushed the vehicle along with his/her feet while steering the front wheel. route The Tour de France was made in 1903 *