The present disclosure provides a captive sprocket system for an engine, comprising: a sprocket including a first sprocket gear, a second sprocket gear and a retaining disc having a diameter and a thickness; a cylinder block having a bore with a central opening and a plurality of threaded bosses, the plurality of threaded bosses together forming an axial support surface and a radial location surface, the axial support surface and the radial location surface being sized to receive the retaining disc of the sprocket to support and locate the sprocket; and a plurality of captivation screws configured to be received by the plurality of threaded bosses, each captivation screw having a head with a lower surface which, when the captivation screw is received by a threaded boss, overlies the retaining disc and retains the sprocket in the bore.

A bicycle sprocket comprises sprocket teeth. The sprocket teeth include at least one first tooth and at least one second tooth. The at least one first tooth has a first radial-tooth height. The at least one first tooth has a first chain-engaging axial width which is smaller than a first distance defined between opposed outer link plates of a bicycle chain and which is larger than a second distance defined between opposed inner link plates of the bicycle chain. The at least one second tooth is adjacent to the first tooth and is disposed on a downstream side in a rotational driving direction of the bicycle sprocket. The at least one second tooth is configured to engage with inner link plates of the bicycle chain. The at least one second tooth has a second radial-tooth height. The first radial-tooth height is greater than the second radial-tooth height.

In a sprocket including a cushion ring coming into contact with link plates of a chain, the cushion ring includes, on an outer circumferential surface, a plurality of convex sections coming into contact with the link plates, and the plurality of convex sections are provided at corresponding positions to tooth tips at identical pitches to a plurality of teeth and include convex sections having different shapes.

Retainer rings for locking in an N-sided shaft to restrict axial movement of components sandwiched between them. The retainer rings have inner edges bounding a central bore. The inner edges are defined by a series of N arcs whose distance from the bore's center decreases gradually along the inner edge from a first end to a second end of each arc. The rings are slid on to the shaft with the corners of the shaft aligned with the first ends of the arcs. Then the rings are rotated on the shafts toward the second ends of the arcs until the corners of the shafts jam against the inner edges. A special spanner wrench can be used to tighten and loosen the rings on the shaft.

Provided is a crank sprocket that allows suppressing a transmission of vibration. The crank sprocket of the present disclosure is mounted to one end side in an axial direction of a crankshaft of an internal combustion engine, and a timing chain is wound around the crank sprocket. The crank sprocket includes a sprocket base body, and a vibration-damping resin layer formed on an inner peripheral surface or a tooth surface of the sprocket base body. The vibration-damping resin layer includes a heat-resistant resin and a vibration damping filler that converts vibration energy into thermal energy.

A toothed wheel system for an internal combustion engine of a motor vehicle is provided. The least one tooth system has a plurality of teeth that follow one another in the circumferential direction of the gear wheel, and at least one elastomer track adjoining the tooth system in the axial direction. The elastomer track is formed as a regular polygon on the outer circumferential side. The number of sides of the polygon correspond to the number of teeth.

To provide a sprocket that reduces the influence of tension fluctuations concurrent with load torque variations, that suppresses noise and vibration, and that prevents an increase in tension fluctuations, noise, and vibration even when the chain tension is low and the load torque is small, or in regions where a chain and the sprocket engage without being affected by the tension. The sprocket has a plurality of teeth mating with the chain that are provided with an equal pitch therebetween, and that include teeth with different working pressure angles relative to the chain.

A chain wheel includes a body and protrusions extending outward along the periphery of the body for receiving links of a chain. The protrusions are connected releasably to the body and are spring-mounted independently of each other in a peripheral direction relative to the body.

In a combination of a sprocket arrangement (128) and a saw chain (16), a sprocket tooth spacing (T1) between consecutive sprocket teeth (40) relates to a drive link spacing between consecutive drive links (30) of the saw chain (16) such that the guide teeth (42) of two or more drive links (30) may enter between a pair of consecutive sprocket teeth (40).

A bicycle sprocket has a rotational center axis. The bicycle sprocket comprises a sprocket body and sprocket teeth. The sprocket teeth include at least one first tooth and at least one second tooth. The at least one first has a first radial-tooth height. The at least one second tooth is adjacent to the first tooth and disposed on a downstream side in a rotational driving direction of the bicycle sprocket. The at least one second tooth has a second radial-tooth height. The first radial-tooth height is greater than the second radial-tooth height. The at least one first tooth includes a tooth tip having an axial center plane in an axial direction. The axial center plane of the tooth tip is offset from the axial center plane of the sprocket body in the axial direction.