A bicycle chain ring, including an inner edge fully circumscribing both an opening and an axis of rotation; an inner surface extending between the inner edge and an outer edge where a plurality of chain ring teeth emanate; and a plurality of ramps disposed about the inner surface, wherein at least one of the plurality of ramps has a lifting surface configured to concurrently engage at least one link of a bicycle chain at two or more distinct pivot points along the length of the chain link to initiate stable lift of the bicycle chain without assistance from any of the plurality of chain ring teeth; wherein the lifting surface has a first end proximate the inner edge and a second end proximate the outer edge.

A gearbox may include a drive spindle and several interconnected gear clusters arranged in a housing. A first of the gear clusters is coaxially fastened to the spindle, and has an outboard gear and an inboard gear. The first gear cluster drives a belt or chain to operate one or more of the other gear clusters, and the inboard gear is physically divided into a plurality of segments. A shifting system for the gearbox includes an actuator configured to urge the segments of the inboard gear of the first gear cluster into and out of the plane of the belt or chain via a toggle and slider mechanism, such that a gear ratio of the gearbox is changeable without displacing the belt or chain out of the plane.

A bicycle cassette comprises two segments that are attached together thereby forming a composite cassette that can be attached to a rear bicycle hub driver body. The bicycle cassette allows for the use of a smaller sprocket on one segment of the cassette because the smaller sprockets can overhang the hub driver body. Specifically, the cassette allows a small 9 or 10 tooth sprocket to overhang the cassette driver body on the bicycle hub by attaching a small sprocket assembly to a larger sprocket assembly using a locking, bayonet style attachment.

A bicycle cassette comprises two segments that are attached together thereby forming a composite cassette that can be attached to a rear bicycle hub driver body. The bicycle cassette allows for the use of a smaller sprocket on one segment of the cassette because the smaller sprockets can overhang the hub driver body. Specifically, the cassette allows a small 9 or 10 tooth sprocket to overhang the cassette driver body on the bicycle hub by attaching a small sprocket assembly to a larger sprocket assembly using a locking, bayonet style attachment.

A rear sprocket assembly comprises a first sprocket, a second sprocket, and at least one tooth-position maintaining member. The at least one tooth-position maintaining member is configured to maintain a relative position between a plurality of first sprocket teeth and a plurality of second sprocket teeth in a circumferential direction with respect to a rotational center axis. The at least one tooth-position maintaining member includes a fixed portion and at least one guide portion. The fixed portion is configured to be fixed to one of the first sprocket and the second sprocket. The at least one guide portion is configured to engage with the other of the first sprocket and the second sprocket such that the other of the first sprocket and the second sprocket is slidable relative to the one of the first sprocket and the second sprocket in the axial direction.

A rear sprocket assembly comprises a first sprocket and a lock device. The lock device includes a first lock member and a second lock member. The first lock member includes a first axial end and a second axial end. The second lock member includes a third axial end and a fourth axial end. The third axial end is configured to be attached to the second axial end of the first lock member in an assembled state where the first sprocket and the lock device are assembled as one unit. The fourth axial end has at least one radial projection configured to abut against a first sprocket in the axial direction in the mounting state. The lock device is configured so that the first sprocket is slidable relative to the lock device in the axial direction in the assembled state and before the mounting state.

A rear sprocket assembly comprises a first sprocket and a lock device. The lock device includes a first lock member and a second lock member. The first lock member includes a first axial end and a second axial end. The second lock member includes a third axial end and a fourth axial end. The third axial end is configured to be attached to the second axial end of the first lock member in an assembled state where the first sprocket and the lock device are assembled as one unit. The fourth axial end has at least one radial projection configured to abut against a first sprocket in the axial direction in the mounting state. The lock device is configured so that the first sprocket is slidable relative to the lock device in the axial direction in the assembled state and before the mounting state.

A drive train for a human-powered vehicle comprises a drive unit, a sprocket arrangement, and a total gear range quotient. The drive unit includes a motor configured to impart propulsion to the human-powered vehicle. The sprocket arrangement is operatively coupled to the drive unit. The sprocket arrangement comprises a plurality of rear sprockets and a plurality of gear ratios respectively corresponding to the plurality of rear sprockets. The plurality of gear ratios includes a largest gear ratio and a smallest gear ratio. The total gear range quotient is obtained by dividing the largest gear ratio by the smallest gear ratio. The total gear range quotient is larger than 5.

The disclosure relates to a torque transmission assembly for a bicycle. The torque transmission assembly includes an adapter device and a driving body that is rigidly connectable to the adapter device in a torque transmitting manner. The adapter device has three support arms that extend with a radial direction component, and the driving body has a corresponding number of support cutouts. The support arms are received in the support cutouts forming a press fit. The torque transmission assembly is characterized in that the press fit of the support arms and support cutouts has two fitting planes, which are parallel to one another and to an imaginary plane containing the axis of rotation of the assembly. There is a clearance between the support arm and support cutout along the radial direction component.

A rear sprocket assembly comprises a first sprocket, a second sprocket, and at least one tooth-position maintaining member. The at least one tooth-position maintaining member is configured to maintain a relative position between a plurality of first sprocket teeth and a plurality of second sprocket teeth in a circumferential direction with respect to a rotational center axis. The at least one tooth-position maintaining member includes a fixed portion and at least one guide portion. The fixed portion is configured to be fixed to one of the first sprocket and the second sprocket. The at least one guide portion is configured to engage with the other of the first sprocket and the second sprocket such that the other of the first sprocket and the second sprocket is slidable relative to the one of the first sprocket and the second sprocket in the axial direction.