Abstract: In a chain shifting device for a bicycle or the like, a bicycle chain extending from the pedal crank can be shifted between the wheels of a chain wheel set positioned on a driven wheel. The chain is trained over the guide wheel and tensioning wheel of a chain guiding and tensioning member. A system of parts guides the chain guiding and tensioning mechanism between its different positions. The system of parts includes a movable joint block connected to the chain guiding and tensioning mechanism and a fixed joint block connected to the bicycle frame. An articulated lever and a guide member are connected by different joints to the movable and fixed joint blocks and are joined together by still another joint. A locking mechanism interlocks two of the parts of the system which are movable relative to one another for securing at least one position of the chain guiding and tensioning mechanism.

Abstract: Two transmission members of a planetary gear transmission in a hub of a driven vehicle wheel are driven simultaneously at different speeds in a forward or backward direction. Driven forward movement of the slower transmission member is transmitted to the hub shell by an overrunning clutch. A second clutch connects the other transmission member to the hub shell when operated by a centrifugal governor at a certain rotary speed. A control device responds to backward rotation of the transmission members, as by back-pedaling, for overriding the governor and for operating the second clutch independently of the rotary speed.