The increase of the rear/center length in an electric-motor-assisted bicycle including a drive unit attached to the vehicle-body frame is minimized. The electric-motor-assisted bicycle (10) includes a vehicle-body frame (12) and a drive unit (20). The drive unit includes two attachment portions (216, 217). The vehicle-body frame includes a bracket (125) and a pair of chain stays (301). The drive unit is attached to the bracket. Each of the chain stays is attached to a position on the bracket that is rearward of the crank axle (22) as measured in the front/rear direction with respect to the bicycle. One attachment portion is located forward of the crank axle as measured in the front/rear direction with respect to the bicycle. The other attachment portion is located rearward of the crank axle as measured in the front/rear direction with respect to the bicycle. At least one of the region (125D) in the bracket to which the chain stay is attached and the region (125F) in the bracket to which the other attachment portion is attached does not overlap a line segment (SL1) connecting the shaft center of the axle (141) of the rear wheel (14R) to the shaft center of the crank axle as viewed from a side of the bicycle.
ELECTRIC-MOTOR-ASSISTED BICYCLE
ELEKTROMOTORUNTERSTÜTZTES FAHRRAD
BICYCLETTE ASSISTÉE PAR MOTEUR ÉLECTRIQUE
2021-02-17
Patent
Electronic Resource
English