Bicycle frame

摘要

A bicycle frame has a front chassis (21) adapted to support thereon a handle bar (46), a front wheel (51) and a seat (45), a rear chassis (27) including a rear wheel support portion adapted to support thereon a rear wheel, and a crank bearing (33) adapted to support therein a drive crank (41) in a rotatable manner so that the rear wheel is driven by the drive crank (41), a pivot bearing arranged between the front chassis and the rear chassis to allow relative rotation between the front chassis and the rear chassis around a substantially horizontal axis of the pivot bearing, and a shock absorber (35) arranged between the front chassis and the rear chassis to absorb a kinetic energy of the relative rotation.