A profiled wheel assembly for coupling to a shaft includes a profiled wheel having a first guide slot extending radially outwardly from a central aperture of the profiled wheel and a first assembly slot spaced apart from and parallel to the first guide slot. A retainer is supported on the profiled wheel for movement between a lock position wherein the retainer axially locks the profiled wheel relative to the shaft and a release position wherein the retainer axially unlocks the profiled wheel relative to the shaft.

A bicycle rear wheel sub-assembly having a sprocket-carrying body, a cogset including a plurality of axially adjacent sprockets with at least three of the plurality of sprockets formed into a monolithic set and a ring nut securing the cogset to the sprocket-carrying body. The ring nut is formed as two parts assembled together—an axially outer first part on which a tubular body and a flange are formed, and an axially inner second part on which a threaded portion is formed. This structure provides a simple and effective coupling of the ring nut with the monolithic sub-set of the cogset and the sprocket-carrying body.

A bicycle rear wheel sub-assembly having a sprocket-carrying body, a cogset including a plurality of axially adjacent sprockets with at least three of the plurality of sprockets formed into a monolithic set and a ring nut securing the cogset to the sprocket-carrying body. The ring nut is formed as two parts assembled together—an axially outer first part on which a tubular body and a flange are formed, and an axially inner second part on which a threaded portion is formed. This structure provides a simple and effective coupling of the ring nut with the monolithic sub-set of the cogset and the sprocket-carrying body.

A cogset with a plurality of sprockets has a subset of the sprockets connected together in a monolithic subset that is mounted directly in engagement with a coupling profile on the radially peripheral surface of a sprocket in the monolithic subset. The direct shape coupling between the sprocket of the monolithic subset and the sprocket-carrying body makes it possible to have very high solidity and rigidity of coupling to ensure the maximum precision of actuation of the gearshift that uses the sub-assembly.

A cogset with a plurality of sprockets has a subset of the sprockets connected together in a monolithic subset that is mounted directly in engagement with a coupling profile on the radially peripheral surface of a sprocket in the monolithic subset. The direct shape coupling between the sprocket of the monolithic subset and the sprocket-carrying body makes it possible to have very high solidity and rigidity of coupling to ensure the maximum precision of actuation of the gearshift that uses the sub-assembly.

A bicycle sprocket assembly comprises a first sprocket and a second sprocket. The first sprocket includes a plurality of first sprocket teeth, a first sprocket inward surface, a first sprocket outward surface, and an axial space. The second sprocket includes a plurality of second sprocket teeth, a second sprocket inward surface, and a second sprocket outward surface. The axial space is defined between the first sprocket outward surface and an axially inward outer link plate in the axial direction while the second sprocket outward surface contacts an axially outward inner link plate in an engagement state where the one of the plurality of the second sprocket teeth is positioned between an axially inward inner link plate and the axially outward inner link plate in the axial direction. The axial space is larger than mm and equal to or smaller than 0.15 mm.

A bicycle sprocket assembly comprises a first sprocket and a second sprocket. The first sprocket includes a plurality of first sprocket teeth, a first sprocket inward surface, a first sprocket outward surface, and an axial space. The second sprocket includes a plurality of second sprocket teeth, a second sprocket inward surface, and a second sprocket outward surface. The axial space is defined between the first sprocket outward surface and an axially inward outer link plate in the axial direction while the second sprocket outward surface contacts an axially outward inner link plate in an engagement state where the one of the plurality of the second sprocket teeth is positioned between an axially inward inner link plate and the axially outward inner link plate in the axial direction. The axial space is larger than mm and equal to or smaller than 0.15 mm.

A sub-assembly is presented, for a bicycle rear wheel, formed by a sprocket-carrying body and a cogset mounted coaxially on the sprocket-carrying body through shape engagement, is sized such that a good compromise is obtained between the ability to house a relatively large number of sprockets and the structural solidity of the sub-assembly.

A sub-assembly is presented, for a bicycle rear wheel, formed by a sprocket-carrying body and a cogset mounted coaxially on the sprocket-carrying body through shape engagement, is sized such that a good compromise is obtained between the ability to house a relatively large number of sprockets and the structural solidity of the sub-assembly.

To provide a simple-structured chain drive mechanism that can reduce the noise generated when the chain sits on the sprocket, prevent deterioration of power transmission efficiency, and retard the progress of wear on the sprocket or chain. The chain drive mechanism includes a sprocket having a plurality of teeth, and a chain having a plurality of link plates and configured to be put around the sprocket. The sprocket includes a pair of flanges protruding circumferentially around the sprocket such as to sandwich the plurality of teeth from sides. The chain includes a pair of seat portions on both sides of the chain so that the flanges abut on the seat portions from a circumferential direction of the sprocket when the chain sits.