Speed change hub used for bicycle, has rotation control portion which is provided in rear end of frame to control operations of rotation gear shift of bicycle

摘要

A rotation control portion (71) is provided in the rear end of a frame to control the operations of a rotation gear shift of a bicycle. The rotation control portion helps a gear shift mechanism (7) in switching and changing the speed of a power transmission route by sliding a clutch through the axial direction of the cam mechanisms (721,733).