bicycle crank

基本解释

The speeder for crank-swinging bicycle without middle axle can make the speed change ratio reach to 10-99 times.
一种曲柄摆动无中轴自行车的增速装置，可使变速比达到10至99倍。
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Men operating a bicycle crank pump refuel cars at the site of a gas station in the earthquake- and tsunami-destroyed town of Minamisanriku, northeastern Japan. (AP Photo/David Guttenfelder)
日本东北部，被地震和海啸摧毁的南三陆町市。人们在一个加油站边运行一个脚踩曲轴泵给汽车加油。
The centre shaft is arranged in the bicycle frame five-way pipe through the ball and the shaft bowl, and the right pedal crank is tightly fixed on the right end of the centre shaft.
中轴通过滚珠及轴碗安装于自行车架五通管内，右脚蹬曲柄紧固于中轴的右端；
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