A bicycle transmission is configured and arranged to improve the durability of the transmission. The transmission basically has a transmission operating device, a support structure, a front input section, an intermediate transmission and a rear output section. The transmission operating device operates the intermediate transmission to change the gear ratio between the front input section and the rear output section. The intermediate transmission has a plurality of drive members arranged to move in the axial direction on an intermediate drive axle in response to its pivotal movement shifting structure. An endless drive member is operatively coupled between a rotatable driving member of the front input section and one of the intermediate drive members. The endless drive member remains substantially in a single plane during shifting of the drive members on the intermediate drive axle.