A bicycle bracket element connects a bicycle frame to a rear gearshift mechanism of a derailleur system. The bracket element includes a first portion which has a cutout for receiving a portion of a bicycle rear wheel axle and a second portion which has a mounting opening to which the rear gearshift mechanism can be secured. The bracket element is formed with a region made from plastic and a region made from metal. The region made from plastic is fixedly connected to the region made from metal.

A bicycle bracket element connects a bicycle frame to a rear gearshift mechanism of a derailleur system. The bracket element includes a first portion which has a cutout for receiving a portion of a bicycle rear wheel axle and a second portion which has a mounting opening to which the rear gearshift mechanism can be secured. The bracket element is formed with a region made from plastic and a region made from metal. The region made from plastic is fixedly connected to the region made from metal.

A bicycle chain tensioner device is basically provided with a base member, a pulley and an electrical storage unit. The pulley is supported by the base member. The pulley includes a dynamo that generates electrical energy in response to the pulley being rotated by a bicycle chain. The electrical storage unit is disposed on the base member and electrically coupled to the dynamo to store electrical energy generated by the dynamo.

A bicycle chain tensioner device is basically provided with a base member, a pulley and an electrical storage unit. The pulley is supported by the base member. The pulley includes a dynamo that generates electrical energy in response to the pulley being rotated by a bicycle chain. The electrical storage unit is disposed on the base member and electrically coupled to the dynamo to store electrical energy generated by the dynamo.

A transmission system for vehicles, including bicycles, is disclosed. The system aligns a chain or other drive means to a center of each of a plurality of provided sprockets, allows for a smaller, lighter and more durable shifter/controller, and reduces various complications associated with cable slack and shifting. A derailleur is provided with linear actuated features to directly translate drive means from one position to another along a desired path.

A transmission system for vehicles, including bicycles, is disclosed. The system aligns a chain or other drive means to a center of each of a plurality of provided sprockets, allows for a smaller, lighter and more durable shifter/controller, and reduces various complications associated with cable slack and shifting. A derailleur is provided with linear actuated features to directly translate drive means from one position to another along a desired path.

A bicycle derailleur includes a lower link member including a position-limiting structure, an external chain-guiding member, a damping shaft, a connection member and a C-shape spring. The external chain-guiding member, connected pivotally with the lower link member, controls a tension of a chain. The connection member is connected with the lower link member. The damping shaft, mounted at one side of the lower link member, is connected pivotally with the external chain-guiding member. The C-shape spring, sleeving the damping shaft, includes a C-clip portion and a first plate portion disposed between the connection member and the position-limiting structure. The first plate portion is extended outward from one end of the C-clip portion in a direction leaving the damping shaft. A friction force upon the external chain-guiding member in the direction to relax the chain is greater than that in the direction to relax the chain.

A bicycle rear derailleur is basically provided with a base member including a frame mounting portion having a mounting opening, and a fastening member extending through the mounting opening of the base member. The fastening member has a first threaded portion and a placement portion adjacent to the first threaded portion. An adjusting member is configured to adjust a position of the bicycle rear derailleur relative to a bicycle. An intermediate member includes a contact portion disposed between the adjusting member and the bicycle. The intermediate member has a second threaded portion configured to threadedly engage with the first threaded portion of the fastening member. The second threaded portion has an innermost diameter that is smaller than the outermost diameter of the first threaded portion. The intermediate member is disposed on the placement portion of the fastening member.

A bicycle eccentric pulley wheel having a chainring, a bearing, and at least one side cover. The chainring is rotatably mounted on the bearing, and the side cover is fixed to the bearing. The side cover is a hollow disk and includes an annular flange formed in an axial direction. The inner side of the annular flange includes a raised portion facing towards a center. The raised portion includes an eccentric hole, which is offset from the center defined by the side cover.

A bicycle eccentric pulley wheel having a chainring, a bearing, and at least one side cover. The chainring is rotatably mounted on the bearing, and the side cover is fixed to the bearing. The side cover is a hollow disk and includes an annular flange formed in an axial direction. The inner side of the annular flange includes a raised portion facing towards a center. The raised portion includes an eccentric hole, which is offset from the center defined by the side cover.