A derailleur system is provided that moves the derailleur cage in a substantially rectilinear path. The derailleur is mounted to a frame having a gear cassette mounted thereon. The gear cassette includes an axis of rotation. The derailleur includes a drive member engaging the gear cassette. The derailleur is positioned on the frame adjacent the gear cassette, and including a spatial linkage having a stationary link, a floating link, and a cage assembly having two pulleys each defining an axis of rotation. The drive member engages each of the pulleys. The path of the floating link is substantially linear through substantially its entire range of motion and variously aligns at least one of the pulleys with the gear cassette.

A derailleur system is provided that moves the derailleur cage in a substantially rectilinear path. The derailleur is mounted to a frame having a gear cassette mounted thereon. The gear cassette includes an axis of rotation. The derailleur includes a drive member engaging the gear cassette. The derailleur is positioned on the frame adjacent the gear cassette, and including a spatial linkage having a stationary link, a floating link, and a cage assembly having two pulleys each defining an axis of rotation. The drive member engages each of the pulleys. The path of the floating link is substantially linear through substantially its entire range of motion and variously aligns at least one of the pulleys with the gear cassette.

A bicycle rear derailleur is provided, including a mounting portion; a linkage mechanism, pivoted to the mounting portion and having an extension portion having a cable fixing point and being located at an inner position relative to an outer side of the linkage mechanism; a guiding mechanism, pivoted to the linkage mechanism and being rotatable about an axis, the guiding mechanism including a first pulley defining a pulley plane and a second pulley, an extension line which is perpendicular to the axis and an axial extension line of the second pulley being defined as a first reference line; wherein when the bicycle rear derailleur is located on an initial position, the cable fixing point is between the first reference line and the mounting portion, and the cable fixing point dose not cross the pulley plane during gearshift of the bicycle rear derailleur relative to rear sprockets.

A bicycle rear derailleur is provided, including a mounting portion; a linkage mechanism, pivoted to the mounting portion and having an extension portion having a cable fixing point and being located at an inner position relative to an outer side of the linkage mechanism; a guiding mechanism, pivoted to the linkage mechanism and being rotatable about an axis, the guiding mechanism including a first pulley defining a pulley plane and a second pulley, an extension line which is perpendicular to the axis and an axial extension line of the second pulley being defined as a first reference line; wherein when the bicycle rear derailleur is located on an initial position, the cable fixing point is between the first reference line and the mounting portion, and the cable fixing point dose not cross the pulley plane during gearshift of the bicycle rear derailleur relative to rear sprockets.

A derailleur system is provided that moves the derailleur cage in a substantially rectilinear path. The derailleur is mounted to a frame having a gear cassette mounted thereon. The gear cassette includes an axis of rotation. The derailleur includes a drive member engaging the gear cassette. The derailleur is positioned on the frame adjacent the gear cassette, and including a spatial linkage having a stationary link, a floating link, and a cage assembly having two pulleys each defining an axis of rotation. The drive member engages each of the pulleys. The path of the floating link is substantially linear through substantially its entire range of motion and variously aligns at least one of the pulleys with the gear cassette.

A derailleur system is provided that moves the derailleur cage in a substantially rectilinear path. The derailleur is mounted to a frame having a gear cassette mounted thereon. The gear cassette includes an axis of rotation. The derailleur includes a drive member engaging the gear cassette. The derailleur is positioned on the frame adjacent the gear cassette, and including a spatial linkage having a stationary link, a floating link, and a cage assembly having two pulleys each defining an axis of rotation. The drive member engages each of the pulleys. The path of the floating link is substantially linear through substantially its entire range of motion and variously aligns at least one of the pulleys with the gear cassette.

A bicycle gearshift mechanism has a base element, a pivot mechanism, a movable element, and a chain guide arrangement. The pivot mechanism connects the base element to the movable element. The chain guide arrangement is connected, rotatably about a rotary axle, to the movable element. The base element comprises a first attachment end, which is coaxial with respect to the rear-wheel axle or axis, and a second attachment end for coupling to the pivot mechanism.

A bicycle gearshift mechanism has a base element, a pivot mechanism, a movable element, and a chain guide arrangement. The pivot mechanism connects the base element to the movable element. The chain guide arrangement is connected, rotatably about a rotary axle, to the movable element. The base element comprises a first attachment end, which is coaxial with respect to the rear-wheel axle or axis, and a second attachment end for coupling to the pivot mechanism.

A rear derailleur with an articulated quadrilateral linkage movable body along respective parallel articulation axes perpendicular to a reference plane (REF), a base body on a bicycle frame along a drop-out axis (F), a chain guide being rotatable around a first rotation axis (R), an upper pulley rotatable around a second rotation axis (RS). The first rotation axis (R) and the second rotation axis (RS) are parallel and spaced by a distance of eccentricity (E). An angle of inclination (Q) of the articulated quadrilateral is defined by the angle that the drop-out axis (F) and the reference plane (REF) form on a plane passing through the drop-out axis (F) and perpendicular to the reference plane (REF). The angle of inclination (Q) being between 5 and 40, including extreme values, and the distance of eccentricity (E) being between 18 mm and 50 mm, including extreme values.

A rear derailleur with an articulated quadrilateral linkage movable body along respective parallel articulation axes perpendicular to a reference plane (REF), a base body on a bicycle frame along a drop-out axis (F), a chain guide being rotatable around a first rotation axis (R), an upper pulley rotatable around a second rotation axis (RS). The first rotation axis (R) and the second rotation axis (RS) are parallel and spaced by a distance of eccentricity (E). An angle of inclination (Q) of the articulated quadrilateral is defined by the angle that the drop-out axis (F) and the reference plane (REF) form on a plane passing through the drop-out axis (F) and perpendicular to the reference plane (REF). The angle of inclination (Q) being between 5 and 40, including extreme values, and the distance of eccentricity (E) being between 18 mm and 50 mm, including extreme values.