Embodiments of a front derailleur gear shifting system including various unique chain guides attached to and operating from a single pivot point. This derailleur system provides a simple, yet, elegant and robust improvement in shifting technique over conventional, lateral motion front derailleurs. Embodiments of open and closed annulus chain guides having specially shaped lifting and pulling surfaces for acting upon a bicycle chain during shifting are also disclosed. Additionally, as an optional enhancement, a dual-sided chain catcher that prevents unintended over-shifts in either direction is disclosed.

Embodiments of a front derailleur gear shifting system including various unique chain guides attached to and operating from a single pivot point. This derailleur system provides a simple, yet, elegant and robust improvement in shifting technique over conventional, lateral motion front derailleurs. Embodiments of open and closed annulus chain guides having specially shaped lifting and pulling surfaces for acting upon a bicycle chain during shifting are also disclosed. Additionally, as an optional enhancement, a dual-sided chain catcher that prevents unintended over-shifts in either direction is disclosed.

A bicycle derailleur is basically provided with a base member, a chain guide, a linkage assembly and a first adjusting member. The chain guide is pivotally supported with respect to the base member between a retracted and an extended position. The linkage assembly includes a first link coupled to the base member about a first pivot axis and coupled to the chain guide about a second pivot axis. The linkage assembly includes a second link coupling the base member to the chain guide. The second link is farther from the bicycle frame than the first link when the base member is mounted to the bicycle frame. The first adjusting member is movably attached to the first link. The first adjusting member is configured to contact one of the base member and the chain guide to restrict movement of the chain guide at one of the retracted and extended positions.

A bicycle derailleur is basically provided with a base member, a chain guide, a linkage assembly and a first adjusting member. The chain guide is pivotally supported with respect to the base member between a retracted and an extended position. The linkage assembly includes a first link coupled to the base member about a first pivot axis and coupled to the chain guide about a second pivot axis. The linkage assembly includes a second link coupling the base member to the chain guide. The second link is farther from the bicycle frame than the first link when the base member is mounted to the bicycle frame. The first adjusting member is movably attached to the first link. The first adjusting member is configured to contact one of the base member and the chain guide to restrict movement of the chain guide at one of the retracted and extended positions.

A motor actuated derailleur for a bicycle gearshift that has a support body adapted for mounting on a bicycle frame. A chain guide moves a bicycle chain between different engaged positions on respective gear wheels. A pair of connecting rods connects said chain guide to said support body with a first connecting rod of said pair of connecting rods being rotatable about a first rotation axis (X) at a first end thereof. A motor housed in said support body has an output shaft able to rotate about a second rotation axis. A transmission between said motor and said first connecting rod is housed in an inner chamber of said support body that comprises at least one adjustable end stop element that prevents the rotation of the output shaft beyond a predetermined rotation angle, in at least one of the two directions of rotation of the output shaft.

A motor actuated derailleur for a bicycle gearshift that has a support body adapted for mounting on a bicycle frame. A chain guide moves a bicycle chain between different engaged positions on respective gear wheels. A pair of connecting rods connects said chain guide to said support body with a first connecting rod of said pair of connecting rods being rotatable about a first rotation axis (X) at a first end thereof. A motor housed in said support body has an output shaft able to rotate about a second rotation axis. A transmission between said motor and said first connecting rod is housed in an inner chamber of said support body that comprises at least one adjustable end stop element that prevents the rotation of the output shaft beyond a predetermined rotation angle, in at least one of the two directions of rotation of the output shaft.

A bicycle derailleur is basically provided with a base member, a chain guide, a linkage assembly and a first adjusting member. The chain guide is pivotally supported with respect to the base member between a retracted and an extended position. The linkage assembly includes a first link coupled to the base member about a first pivot axis and coupled to the chain guide about a second pivot axis. The linkage assembly includes a second link coupling the base member to the chain guide. The second link is farther from the bicycle frame than the first link when the base member is mounted to the bicycle frame. The first adjusting member is movably attached to the first link. The first adjusting member is configured to contact one of the base member and the chain guide to restrict movement of the chain guide at one of the retracted and extended positions.

A bicycle derailleur is basically provided with a base member, a chain guide, a linkage assembly and a first adjusting member. The chain guide is pivotally supported with respect to the base member between a retracted and an extended position. The linkage assembly includes a first link coupled to the base member about a first pivot axis and coupled to the chain guide about a second pivot axis. The linkage assembly includes a second link coupling the base member to the chain guide. The second link is farther from the bicycle frame than the first link when the base member is mounted to the bicycle frame. The first adjusting member is movably attached to the first link. The first adjusting member is configured to contact one of the base member and the chain guide to restrict movement of the chain guide at one of the retracted and extended positions.