Abstract: A bicycle derailleur is provided that basically includes a base member, a movable member, a chain guide, a biasing element and a rotational resistance structure. The base member is configured to be mounted to a bicycle. The movable member is movably coupled to the base member. The chain guide is pivotally coupled to the movable member to rotate around a rotational axis with respect to the movable member. The biasing element biases the chain guide in a first rotational direction around the rotational axis with respect to the movable member. The rotational resistance structure is operatively arranged between the movable member and the chain guide to frictionally provide rotational resistance to the chain guide around the rotational axis in a second rotational direction. The rotational resistance structure applies the rotational resistance at an area disposed radially outward of the biasing element with respect to the rotational axis.

Abstract: A bicycle derailleur is basically provided with a main body, a chain cage, a first pulley, a second pulley and a chain contact member. The main body is configured to be mounted to a bicycle. The chain cage is pivotally coupled to the main body movement between at least a first orientation and a second orientation. The first pulley is rotatably coupled to one of the chain cage and the main body. The second pulley is rotatably mounted to the chain cage to move therewith relative to the main body. The chain contact member is coupled to the main body. The chain contact member includes a non-rotatable chain contact portion that projects into a chain path between the first and second pulleys while the chain cage is in the first orientation, and that is located outside of the chain path between the first and second pulleys while the chain cage is in the second orientation.

Abstract: A chain tensioning device is basically provided with a main body, a chain guide and a rotary fluid damper unit. The main body is configured to be mounted to a bicycle. The chain guide is pivotally coupled to the main body to rotate around a rotational axis with respect to the main body. The rotary fluid damper unit is operatively connected between the main body and the chain guide to provide rotational resistance to the chain guide around the rotational axis. The rotary fluid damper unit is a separate unit from the main body, the rotary fluid damper unit being detachably mounted on the main body.

Abstract: A bicycle derailleur comprises a base member adapted to be mounted to a bicycle, a movable member movably coupled to the base member, a chain guide coupled to the movable member for rotation around a rotational axis, a resistance applying element that applies resistance to rotational movement of the chain guide, and a resistance control element. The resistance control element applies a force to the resistance applying element in a direction that is non-parallel with the rotational axis, without any manual operations, to prevent a reduction in the resistance to rotational movement of the chain guide applied by the resistance applying element.

Abstract: A bicycle rear derailleur is basically provided with a base member, a cable operated structure, a movable member and a biasing member. The movable member is movably supported to the base member by the cable operated structure to move between a plurality of shift stage positions with respect to the base member. The biasing member is interposed between the first and second link members such that the movable member is biased towards one of a top shift stage position and a low shift stage position. The cable operated structure and the biasing member configured balance an operation energy used for shifting between each of the shift stage positions.

Abstract: A bicycle derailleur comprises a base member adapted to be mounted to a bicycle, a movable member, a linkage mechanism coupled between the base member and the movable member so that the movable member moves relative to the base member, and a chain guide coupled to the movable member for movement relative to the movable member. A position-fixing member selectively fixes a position of the movable member relative to the chain guide.

Abstract: A rear derailleur includes a base member, a movable member, a linkage and an electric motor unit. The base member includes a bicycle mounting portion for attaching to a bicycle. The movable member includes a chain guide having a first pulley that rotates around a first pulley axis in a center pulley plane that bisects the first pulley. The linkage movably supports the movable member relative to the base member. The electric motor unit is stationary with respect to at least a part of the base member and operatively coupled to the linkage to move the movable member relative to the base member between an outermost lateral position and an innermost lateral position. The electric motor unit is at least partially disposed inward of the center pulley plane while the movable member is disposed in the outermost lateral position.

Abstract: A chain tensioning device is basically provided with a main body, a chain guide and a rotary fluid damper unit. The main body is configured to be mounted to a bicycle. The chain guide is pivotally coupled to the main body to rotate around a rotational axis with respect to the main body. The rotary fluid damper unit is operatively connected between the main body and the chain guide to provide rotational resistance to the chain guide around the rotational axis. The rotary fluid damper unit is a separate unit from the main body, the rotary fluid damper unit being detachably mounted on the main body.

Abstract: A chain tensioning device is basically provided with a main body, a chain guide, a rotary fluid damper unit and a rotational resistance adjustment device. The main body is configured to be mounted to a bicycle. The chain guide is pivotally coupled to the main body to rotate around a rotational axis with respect to the main body. The rotary fluid damper unit is operatively connected between the main body and the chain guide to provide rotational resistance to the chain guide around the rotational axis. The rotational resistance adjustment device is operatively connected to the rotary fluid damper unit to change a rotational resistance setting of the rotary fluid damper unit with the rotational resistance adjustment device in an operative state.

Abstract: A bicycle derailleur includes a base member, a movable member, a motor unit, a linkage and a saver mechanism. The linkage includes a first link that includes a first linking member and a second linking member. The first linking member is pivotally connected to the movable member. The second linking member is pivotally connected to the base member, and is attached to the first linking member. The saver mechanism includes an output member movably operated by the motor unit, a drive link movably mounted on the first link between a drive transmitting position that connects a drive force of the motor to the first link and a non-drive transmitting position that disconnect the drive force of the motor from the first link, and a biasing element biasing the drive link into engagement with the output member to maintain the drive link in the drive transmitting position.

Abstract: A bicycle derailleur is basically provided with a main body, a chain cage, a first pulley, a second pulley and a chain contact member. The main body is configured to be mounted to a bicycle. The chain cage is pivotally coupled to the main body movement between at least a first orientation and a second orientation. The first pulley is rotatably coupled to one of the chain cage and the main body. The second pulley is rotatably mounted to the chain cage to move therewith relative to the main body. The chain contact member is coupled to the main body. The chain contact member includes a non-rotatable chain contact portion that projects into a chain path between the first and second pulleys while the chain cage is in the first orientation, and that is located outside of the chain path between the first and second pulleys while the chain cage is in the second orientation.

Abstract: A bicycle derailleur is provided that basically includes a base member, a movable member, a chain guide, a biasing element and a rotational resistance structure. The base member is configured to be mounted to a bicycle. The movable member is movably coupled to the base member. The chain guide is pivotally coupled to the movable member to rotate around a rotational axis with respect to the movable member. The biasing element biases the chain guide in a first rotational direction around the rotational axis with respect to the movable member. The rotational resistance structure is operatively arranged between the movable member and the chain guide to frictionally provide rotational resistance to the chain guide around the rotational axis in a second rotational direction. The rotational resistance structure applies the rotational resistance at an area disposed radially outward of the biasing element with respect to the rotational axis.

Abstract: A bicycle derailleur basically includes a base member, a movable member, a chain guide, a friction element and a motor. The base member is configured to be mounted to a bicycle. The movable member is movably coupled to the base member. The chain guide is coupled to the movable member to rotate around a rotational axis with respect to the movable member. The friction element is operatively arranged between the movable member and the chain guide to frictionally provide rotational resistance in a first rotational direction of the chain guide. The motor is operatively coupled to the movable member to move the movable member with respect to the base member.

Abstract: A rear derailleur is basically provided with a base member, a movable member, a chain guide, a friction element, a one-way clutch and an electric actuator. The base member is configured to be mounted to a bicycle. The movable member is movably coupled to the base member. The chain guide is coupled to the movable member to rotate around a rotational axis with respect to the movable member. The friction element is operatively arranged between the movable member and the chain guide to frictionally provide rotational resistance in a first rotational direction of the chain guide. The one-way clutch is operatively disposed between movable member and the chain guide to engage the friction element as the chain guide rotates in the first rotational direction. The electric actuator is operatively coupled to the one-way clutch to control the one-way clutch between a clutch-on mode and a clutch-off mode.

Abstract: A bicycle derailleur comprises a base member, a movable member movably coupled to the base member, and a chain guide coupled to the movable member for rotation around a rotational axis. A resistance applying element applies resistance to rotational movement of the chain guide. A resistance control element moves between at least different first and second positions, wherein the resistance control element is disposed so that the resistance control element can be directly manipulated by a user without using a tool. The resistance control element is operatively coupled to the resistance applying element so that the resistance applying element applies different first and second resistances to rotational movement of the chain guide when the resistance control element is disposed in the respective first and second positions.

Abstract: A bicycle derailleur comprises a base member, a movable member movably coupled to the base member, and a chain guide coupled to the movable member for rotation around a rotational axis. A resistance applying element applies resistance to rotational movement of the chain guide, and a resistance control element moves between at least different first and second positions. The resistance control element is operatively coupled to the resistance applying element so that the resistance applying element applies different first and second resistances to rotational movement of the chain guide when the resistance control element is disposed in the respective first and second positions.

Abstract: A rear derailleur includes a base member, a movable member, a linkage and an electric motor unit. The base member includes a bicycle mounting portion for attaching to a bicycle. The movable member includes a chain guide having a first pulley that rotates around a first pulley axis in a center pulley plane that bisects the first pulley. The linkage movably supports the movable member relative to the base member. The electric motor unit is stationary with respect to at least a part of the base member and operatively coupled to the linkage to move the movable member relative to the base member between an outermost lateral position and an innermost lateral position. The electric motor unit is at least partially disposed inward of the center pulley plane while the movable member is disposed in the outermost lateral position.

Abstract: A rear derailleur is basically provided with a base member, a movable member, a chain guide, a friction element, a one-way clutch and an electric actuator. The base member is configured to be mounted to a bicycle. The movable member is movably coupled to the base member. The chain guide is coupled to the movable member to rotate around a rotational axis with respect to the movable member. The friction element is operatively arranged between the movable member and the chain guide to frictionally provide rotational resistance in a first rotational direction of the chain guide. The one-way clutch is operatively disposed between movable member and the chain guide to engage the friction element as the chain guide rotates in the first rotational direction. The electric actuator is operatively coupled to the one-way clutch to control the one-way clutch between a clutch-on mode and a clutch-off mode.

Abstract: A bicycle rear derailleur includes a base member, a movable member, a linkage and a motor unit. The base member is configured to be mounted to a bicycle. The movable member is movably coupled to the base member. The linkage includes an outer link pivotally connected to the base member about a first pivot axis and pivotally connected to the movable member about a second pivot axis, and an inner link pivotally connected the base member and the movable member. The motor unit includes an output shaft having a rotational axis being parallel to one of the first pivot axis and the second pivot axis. The output shaft of the motor unit drives the outer link to move the movable member with respect to the base member. The inner link moves in response to movement of the outer link.

Abstract: A bicycle derailleur includes a base member, a movable member, a motor unit, a linkage and a saver mechanism. The linkage includes a first link that includes a first linking member and a second linking member. The first linking member is pivotally connected to the movable member. The second linking member is pivotally connected to the base member, and is attached to the first linking member. The saver mechanism includes an output member movably operated by the motor unit, a drive link movably mounted on the first link between a drive transmitting position that connects a drive force of the motor to the first link and a non-drive transmitting position that disconnect the drive force of the motor from the first link, and a biasing element biasing the drive link into engagement with the output member to maintain the drive link in the drive transmitting position.