A chain tensioner device includes: a threaded bolt (3) for adjusting tension on a chain, that remains inserted in a part (4) integral with the wheel shaft (5), arranged in horizontal position, so that the tip (3a) of the bolt (3), presses on a second part (6) integral at the opposite end of the gear, so that tightening or loosening the bolt (3) determines a gap between both parts (4, 6) to regulate the tension and a discretization mechanism of the gap between the first part (4) and the second part (6) that includes at least a retractable element (8) either in the bolt (3) or in the first part (4) that contacts and is fitted in one of the series of slots (11) provided either in the bolt (3) or in the first part (4) so that it is possible to know the tightening or loosening of the bolt (3) applicable in each action.

A chain tensioner device includes: a threaded bolt (3) for adjusting tension on a chain, that remains inserted in a part (4) integral with the wheel shaft (5), arranged in horizontal position, so that the tip (3a) of the bolt (3), presses on a second part (6) integral at the opposite end of the gear, so that tightening or loosening the bolt (3) determines a gap between both parts (4, 6) to regulate the tension and a discretization mechanism of the gap between the first part (4) and the second part (6) that includes at least a retractable element (8) either in the bolt (3) or in the first part (4) that contacts and is fitted in one of the series of slots (11) provided either in the bolt (3) or in the first part (4) so that it is possible to know the tightening or loosening of the bolt (3) applicable in each action.

The invention relates to a belt drive (24) with (a) a first pulley wheel (12) in the form of a drive sprocket with drive teeth (16), (b) a second pulley wheel in the form of an output sprocket (18) and (c) a toothed belt (22) that (i) connects the drive sprocket (12) and the output sprocket (18) for transmitting a force and (ii) has a belt back (38) and (iii) a plurality of teeth (34), wherein a tooth base (36) is situated between two adjacent teeth. According to the invention, (d) the toothed belt (22) comprises a plurality of recesses (26), each of which is configured in a tooth base (36), and (e) at least one pulley wheel features guide projections (28) for engaging in the recesses (26).

The invention relates to a belt drive (24) with (a) a first pulley wheel (12) in the form of a drive sprocket with drive teeth (16), (b) a second pulley wheel in the form of an output sprocket (18) and (c) a toothed belt (22) that (i) connects the drive sprocket (12) and the output sprocket (18) for transmitting a force and (ii) has a belt back (38) and (iii) a plurality of teeth (34), wherein a tooth base (36) is situated between two adjacent teeth. According to the invention, (d) the toothed belt (22) comprises a plurality of recesses (26), each of which is configured in a tooth base (36), and (e) at least one pulley wheel features guide projections (28) for engaging in the recesses (26).

A chain damper for use with a bicycle may include a base having an attachment region that is configured to be attached to a bicycle and a chain receiving portion extending from the base in a first direction. The chain receiving portion can include a chain damping surface that includes a resiliently deformable damping material and at least partially bounds a chain receiving aperture. The chain receiving aperture may extend in an axial direction and may be configured so that when the chain damper is attached to the bicycle the axial direction is substantially aligned with the primary chain direction and the chain damping surface is spaced apart from the chain travel path.

A bicycle includes a front wheel, a rear wheel, a frame comprising a main frame section and an articulated frame section, the articulated frame section comprising: a lower arm rotatably supported on a first axis by the main frame section, an upper frame link, the rotatably supported on a second axis by the main frame section, an upper arm rotatably connected to the upper frame link on a third axis, an upper butt joint rotatably connected to the upper frame link and the upper arm on the third axis, and a lower butt joint rotatably connected to the main frame portion and the lower arm on the first axis, and a shock absorber having a first end rotatably supported on a fourth axis by the main frame portion and a second end connected to a fifth axis from the upper butt joint and the lower butt joint ndung is held rotatable.

A bicycle includes a front wheel, a rear wheel, a frame comprising a main frame section and an articulated frame section, the articulated frame section comprising: a lower arm rotatably supported on a first axis by the main frame section, an upper frame link, the rotatably supported on a second axis by the main frame section, an upper arm rotatably connected to the upper frame link on a third axis, an upper butt joint rotatably connected to the upper frame link and the upper arm on the third axis, and a lower butt joint rotatably connected to the main frame portion and the lower arm on the first axis, and a shock absorber having a first end rotatably supported on a fourth axis by the main frame portion and a second end connected to a fifth axis from the upper butt joint and the lower butt joint ndung is held rotatable.

A rear derailleur includes a base member mountable to a bicycle frame, a movable member movably coupled to the base member, and a pivot member rotatably coupled to the movable member. The rear derailleur also includes a chain guide assembly rotatably connected to the movable member via the pivot member. The rear derailleur includes a damper device disposed within the movable member. The damper device is operable to apply a damping force to the chain guide assembly when the chain guide assembly rotates. The damper device includes a friction member having a friction surface. A first portion of the friction surface is in frictional engagement with the pivot member, and a second portion of the friction surface is in frictional engagement with the movable member. The friction device is disposed within the movable member at a distance relative to the biasing device in an axial direction along the pivot member.

A rear derailleur includes a base member mountable to a bicycle frame, a movable member movably coupled to the base member, and a pivot member rotatably coupled to the movable member. The rear derailleur also includes a chain guide assembly rotatably connected to the movable member via the pivot member. The rear derailleur includes a damper device disposed within the movable member. The damper device is operable to apply a damping force to the chain guide assembly when the chain guide assembly rotates. The damper device includes a friction member having a friction surface. A first portion of the friction surface is in frictional engagement with the pivot member, and a second portion of the friction surface is in frictional engagement with the movable member. The friction device is disposed within the movable member at a distance relative to the biasing device in an axial direction along the pivot member.

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.