The invention relates to a bike with an assistor, in particular to a bicycle, tricycle or tetra-cycle with an assistor, comprising a frame, a rear axle, a front axle and a middleshaft.
本发明涉及一种具有助力装置的脚踏车，尤其是指具有助力 装置的自行车、三轮脚踏车或四轮脚踏车。
2
The race-proven pulleys and drive belts have been carried over from the T1 platform and the super-efficient 20T middleshaft pulley guarantees the best belt wrapping and highly-efficient drivetrain.
Two-way pressure has mounted on ball bearings between the shaft and two outer rings, in the middle ring and outer ring were added between the steel ball, able to withstand the two-way axial load.