摘要 |
Disclosed is a bicycle chain transmission, which comprises a crank 4 fastened in a bearing block on the outer side of a chain wheel and connected with a side projection 231 of a ball bearing which is mounted on a connector 20 which is eccentrically fastened in the bottom bracket axle of a bicycle. The rotation of the connector drives the ball bearing 23 to rotate eccentrically and to drive the crank 4 to automatically change its arm of force so as to minimize energy consumption in pedaling. <IMAGE> |