Abstract: An automatic variable speed lever action drive for a pedal operated vehicle, in which a pedal lever pivotally mounted on each side of the vehicle frame is connected in part by an extensible and retractable cable to a driven wheel, the lever having a direct driving connection to the cable through a roller on a tension spring for deflecting the cable to varying degrees in accordance with the tension load on the cable. The lever has a knee joint type double pivot and is guided through the actuating stroke to substantially linearize the actual path of the pedal.

Abstract: A derailleur gear shift mechanism for a bicycle, in which the drive chain transfer unit for moving the chain to selected gears is operated by a rigid push-pull rod actuating linkage. An actuating lever, accessibly mounted on the bicycle frame, is indexed to specific positions at which the linkage holds the chain transfer unit in accurate alignment with individual rear wheel drive sprockets. The mechanism is adaptable to many existing derailleur gear assemblies.