A bicycle rear sprocket assembly 28 comprises a sprocket carrier 31, at least one metallic support 33, and at least one rear sprocket 28a-28h. The sprocket carrier 31 is made of a non-metallic material. The at least one metallic support 33 is attached to at least one of a first circumferentially facing surface 41 and a second circumferentially facing surface 43 of at least one mounting arm 39 of the sprocket carrier 31. The at least one rear sprocket 28a-28h is made of a metallic material. A sprocket body 51 of the at least one rear sprocket 28a-28h is attached to the at least one metallic support 33.

A bicycle sprocket comprises a sprocket body and a plurality of sprocket teeth. The plurality of sprocket teeth includes at least one first axially recessed upshifting-facilitation tooth with respect to a rotational center axis. The plurality of sprocket teeth includes at least one first axially recessed downshifting-facilitation tooth with respect to the rotational center axis. The at least one first axially recessed downshifting-facilitation tooth is adjacent to the at least one first axially recessed upshifting-facilitation tooth without another tooth therebetween in a circumferential direction with respect to the rotational center axis. The at least one first axially recessed upshifting-facilitation tooth and the at least one first axially recessed downshifting-facilitation tooth provide a first continuous recess extending in the circumferential direction.

A bicycle sprocket comprises a sprocket body and a plurality of sprocket teeth. The plurality of sprocket teeth includes at least one first axially recessed upshifting-facilitation tooth with respect to a rotational center axis. The plurality of sprocket teeth includes at least one first axially recessed downshifting-facilitation tooth with respect to the rotational center axis. The at least one first axially recessed downshifting-facilitation tooth is adjacent to the at least one first axially recessed upshifting-facilitation tooth without another tooth therebetween in a circumferential direction with respect to the rotational center axis. The at least one first axially recessed upshifting-facilitation tooth and the at least one first axially recessed downshifting-facilitation tooth provide a first continuous recess extending in the circumferential direction.

A multi-sprocket arrangement for a rear wheel hub of a bicycle may have improved gearshift characteristics, reduced vibrations during skewed running, and improved wear characteristics. The multi-sprocket arrangement includes a multiplicity of sprockets of different diameters, wherein at least one of the sprockets has a multiplicity of teeth. Also on the circumference of said sprocket, as viewed in a circumferential direction, at least one sequence of teeth is provided in which, with regard to their material thickness, a thin tooth is followed by a thick tooth which is followed in turn by another thin tooth.

A multi-sprocket arrangement for a rear wheel hub of a bicycle may have improved gearshift characteristics, reduced vibrations during skewed running, and improved wear characteristics. The multi-sprocket arrangement includes a multiplicity of sprockets of different diameters, wherein at least one of the sprockets has a multiplicity of teeth. Also on the circumference of said sprocket, as viewed in a circumferential direction, at least one sequence of teeth is provided in which, with regard to their material thickness, a thin tooth is followed by a thick tooth which is followed in turn by another thin tooth.

A bicycle sprocket includes a sprocket body, a tooth ring, and at least one non-threaded fastener. The sprocket body is made of a first material and has a rotational center axis. A central portion of the sprocket body has a central opening through which the rotational center axis passes. The sprocket body further includes a plurality of arm portions that extend radially outward from the central portion with respect to the rotational center axis. Each arm portion includes a sprocket body attachment portion. The tooth ring is made of a second material different from the first material and includes an annular portion. The annular portion includes a plurality of tooth ring attachment portions and a plurality of chain-driving teeth extending radially outward from the annular portion. The non-threaded fastener fixedly connects a sprocket body attachment portion and to a corresponding tooth ring attachment portion.

A bicycle sprocket includes a sprocket body, a tooth ring, and at least one non-threaded fastener. The sprocket body is made of a first material and has a rotational center axis. A central portion of the sprocket body has a central opening through which the rotational center axis passes. The sprocket body further includes a plurality of arm portions that extend radially outward from the central portion with respect to the rotational center axis. Each arm portion includes a sprocket body attachment portion. The tooth ring is made of a second material different from the first material and includes an annular portion. The annular portion includes a plurality of tooth ring attachment portions and a plurality of chain-driving teeth extending radially outward from the annular portion. The non-threaded fastener fixedly connects a sprocket body attachment portion and to a corresponding tooth ring attachment portion.

A chain ring for engaging a chain link of a chain, the 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 includes a lifting surface for initiating lift of a chain without assistance from the plurality of chain ring teeth. The lifting surface extends radially along the inner surface toward the outer edge, and the at least one ramp has a first end proximate the inner edge and a second end proximate the outer edge. The second end of the at least one lifting surface terminates before reaching the bottom of a trough positioned between two or more of the plurality of chain ring teeth.

A chain ring for engaging a chain link of a chain, the 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 includes a lifting surface for initiating lift of a chain without assistance from the plurality of chain ring teeth. The lifting surface extends radially along the inner surface toward the outer edge, and the at least one ramp has a first end proximate the inner edge and a second end proximate the outer edge. The second end of the at least one lifting surface terminates before reaching the bottom of a trough positioned between two or more of the plurality of chain ring teeth.

The present disclosure describes a gearshift mechanism for adjusting a gear ratio between a traction means, such as a chain, and a multi-sprocket gear set which can be rotated around an axle. The gearshift mechanism is configured to move the traction means in relation to the sprockets, such that an adjustment element is moved into the rolling motion of the traction means, thereby causing movement off of one sprocket and movement onto another sprocket.