A derailleur basically includes a base member, a movable member and a linkage assembly. The base member includes a first base member connecting section and a second base member connecting section. The movable member includes a first movable member connecting section and a second movable member connecting section. The linkage assembly includes an inner link member and an outer link member. The outer link is pivotally coupled to the second base member connecting section about a third pivot axis. The outer link is pivotally coupled to the second movable member connecting section about a fourth pivot axis. The outer link member has a power source receiving part that is configured to be arranged such that the power source receiving part traverses a reference line extending between the third pivot axis and the fourth pivot axis.

A bicycle electric/electronic derailleur has mutually movable components, and a geared motor for controlling the mutual motion of the components. The geared motor includes an electric motor having a drive shaft, an output shaft and a speed reducer including at least one gear between the drive shaft and the output shaft. The output shaft defines at least in part one of the articulation axes. The electric motor is rigidly connected to a first component, and a second component integrally rotates with the output shaft. The derailleur further includes a magnetic rotary encoder for transducing a quantity related to the mutual motion of the components. The encoder includes a permanent magnet and a sensor responding to the changes in the magnetic field of the magnet. The magnet is a disc, cylindrical or annular magnet having diametral magnetization, and is coaxial with and arranged to integrally rotate with the output shaft.

A rear gearshift mechanism for installation on a bicycle frame coaxial with a rear-wheel axis has a base element, a pivot mechanism, a movable element and a chain guide. The base element includes an attachment end for installation on the bicycle frame. A first arm and a second arm of the attachment end are arranged spaced apart from one another in an axial direction and, by an associated adapter which has a thread, are configured for the installation of the gearshift mechanism on an associated bracket portion, in particular a dropout or frame hanger. The first arm is arranged on an inner side of the bracket portion, and the second arm is arranged on an outer side of the bracket portion. The base element is designed with a setting device by which the base element can be pivoted in a chain tensioning direction.

A rear gearshift mechanism for installation on a bicycle frame coaxial with a rear-wheel axis has a base element, a pivot mechanism, a movable element and a chain guide. The base element includes an attachment end for installation on the bicycle frame. A first arm and a second arm of the attachment end are arranged spaced apart from one another in an axial direction and, by an associated adapter which has a thread, are configured for the installation of the gearshift mechanism on an associated bracket portion, in particular a dropout or frame hanger. The first arm is arranged on an inner side of the bracket portion, and the second arm is arranged on an outer side of the bracket portion. The base element is designed with a setting device by which the base element can be pivoted in a chain tensioning direction.

A bicycle derailleur includes a base member mountable to a bicycle frame and a cage assembly moveably coupled to the base member. One or both of a motor and/or electrical generator system may be coupled to and moveable with the cage assembly. The motor is operable to move the cage assembly. The electrical generator system includes a generator and a generator drive system.

A bicycle derailleur includes a base member mountable to a bicycle frame and a cage assembly moveably coupled to the base member. One or both of a motor and/or electrical generator system may be coupled to and moveable with the cage assembly. The motor is operable to move the cage assembly. The electrical generator system includes a generator and a generator drive system.

A bicycle derailleur comprises a base member, a movable member, a motor unit, and a controller. The controller is configured to control the motor unit to rotate an output shaft of the motor unit at a first maximum voltage during a first shifting operation of the chain in a first shifting direction. The controller is configured to control the motor unit to rotate the output shaft of the motor unit at a second maximum voltage during a second shifting operation of the chain in a second shifting direction. The first maximum voltage is different from the second maximum voltage.

A bicycle gearshift is operated by imposing on the chain guide a primary displacement in the axial direction with respect to a cogset, to move the chain between the sprockets. Simultaneously with imposing on the primary displacement imposing on the chain guide a secondary displacement in the radial direction with respect to the cogset. The secondary displacement is of a greater size when the primary displacement takes place in the area of the cogset with the larger sprockets whereas it is of a smaller size when the primary displacement takes place in the area of the cogset with the smaller sprockets.

A bicycle gearshift is operated by imposing on the chain guide a primary displacement in the axial direction with respect to a cogset, to move the chain between the sprockets. Simultaneously with imposing on the primary displacement imposing on the chain guide a secondary displacement in the radial direction with respect to the cogset. The secondary displacement is of a greater size when the primary displacement takes place in the area of the cogset with the larger sprockets whereas it is of a smaller size when the primary displacement takes place in the area of the cogset with the smaller sprockets.

A bicycle rear derailleur comprises a base member, a linkage structure, a movable member, a first pulley assembly, and a second pulley assembly. The first pulley assembly includes a first pulley support and a first toothed pulley. The first pulley support is pivotally coupled to the movable member about a first pivot axis. The first toothed pulley is rotatably coupled to the first pulley support about a first pulley axis spaced apart from the first pivot axis. The second pulley assembly includes a second pulley support, a second toothed pulley, and a third toothed pulley. The second pulley support is pivotally coupled to the movable member about a second pivot axis. The second toothed pulley is rotatably coupled to the second pulley support about a second pulley axis. The third toothed pulley is rotatably coupled to the second pulley support about a third pulley axis.