A bicycle rear derailleur includes a movable member and a chain guide assembly rotatably connected to the movable member. The bicycle rear derailleur also includes a pivot member non-rotatably coupled to the chain guide assembly and having an outer annular surface, a biasing device configured to bias the chain guide assembly in a first rotational direction relative to the movable member, and a damper device disposed between the chain guide assembly and the movable member. The damper device is operable to apply a damping force to the chain guide assembly when the chain guide assembly rotates in a second rotational direction relative to the movable member. The damper device includes a friction device that is radially inner relative to the biasing device. The friction device includes a friction member having at least one friction surface biased against and in frictional engagement with the pivot member.

A bicycle rear derailleur includes a movable member and a chain guide assembly rotatably connected to the movable member. The bicycle rear derailleur also includes a pivot member non-rotatably coupled to the chain guide assembly and having an outer annular surface, a biasing device configured to bias the chain guide assembly in a first rotational direction relative to the movable member, and a damper device disposed between the chain guide assembly and the movable member. The damper device is operable to apply a damping force to the chain guide assembly when the chain guide assembly rotates in a second rotational direction relative to the movable member. The damper device includes a friction device that is radially inner relative to the biasing device. The friction device includes a friction member having at least one friction surface biased against and in frictional engagement with the pivot member.

In an adjustment mode for a derailleur of a bicycle, acceleration values from an accelerometer of the derailleur are sampled as the derailleur moves through sprockets of a rear sprocket assembly. Acceleration signal powers are identified based on the sampled acceleration values, and potential rasping positions are identified based on thresholding of the acceleration signal powers. The identified potential rasping positions are compared to expected rasping positions, and adjustment for the derailleur is set based on a minimum error between the identified potential rasping positions and the expected rasping positions.

In an adjustment mode for a derailleur of a bicycle, acceleration values from an accelerometer of the derailleur are sampled as the derailleur moves through sprockets of a rear sprocket assembly. Acceleration signal powers are identified based on the sampled acceleration values, and potential rasping positions are identified based on thresholding of the acceleration signal powers. The identified potential rasping positions are compared to expected rasping positions, and adjustment for the derailleur is set based on a minimum error between the identified potential rasping positions and the expected rasping positions.

A rear derailleur is provided for a bicycle. The rear derailleur has an upper alignment assembly and a lower alignment assembly pivotally connected via a linkage assembly. The upper alignment assembly is pivotally attached to the bicycle along a b-knuckle mounting axis, and the upper alignment assembly includes a motor assembly to pivot the upper alignment assembly along an upper rotatable axis that is generally perpendicular to the b-knuckle mounting axis. The lower alignment assembly is pivotally attached to a pulley assembly along a p-knuckle mounting axis, and the lower alignment assembly includes a motor assembly to pivot the lower alignment assembly along a lower rotatable axis that is generally perpendicular to the p-knuckle mounting axis.

A shifting control device comprises a controller configured to control an actuator of a gear shifting device to arrange a chain guide of the gear shifting device on a plurality of gear positions. The controller is configured to control the actuator to temporarily arrange the chain guide on a first temporary position in a multistage gear shift operation before stopping the chain guide at the first target gear position. The controller is configured to temporarily arrange the chain guide on a second temporary position in a single gear shift operation before stopping the chain guide at the second target gear position. The first temporary position is offset from the second temporary position in the gear shift direction if the first target gear position is the first target gear position and the second target gear position correspond to the same gear position of the plurality of gear positions.

A method for controlling a motor of a derailleur of a bicycle electronic gearshift during a displacement from an initial position (A) towards a destination position (B) includes the step of feedback controlling the current (I(t)) absorbed by the motor. A controller of an electric motor of a derailleur of a bicycle electronic gearshift is configured to carry out a feedback control of the current (I(t)) absorbed by the motor during a displacement from an initial position (A) towards a destination position (B).

A method for controlling a motor of a derailleur of a bicycle electronic gearshift during a displacement from an initial position (A) towards a destination position (B) includes the step of feedback controlling the current (I(t)) absorbed by the motor. A controller of an electric motor of a derailleur of a bicycle electronic gearshift is configured to carry out a feedback control of the current (I(t)) absorbed by the motor during a displacement from an initial position (A) towards a destination position (B).

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.

The disclosure provides a bicycle rear derailleur including a linkage assembly, a chain guiding assembly, a first assembling component, a first elastic component and a locking mechanism. The linkage assembly is a four-link mechanism and includes a fixed component, a movable component, a first link and a second link. The chain guiding assembly is pivotably connected to the movable component. The first assembling component is pivotably connected to the movable component and disposed between the first assembling component and the chain guiding assembly. The opposite ends of the first elastic component are respectively fixed to the movable component and the first assembling component so as to provide a torque that allows the first assembling component to be pivotable with respect to the movable component.