A crank set for a two-wheeler, the crank set comprising a crank with a crank spider, a chainring and a chain guard ring, the chainring being fastened to the crank spider by fastening elements, and the fastening elements pressing the chainring and the crank spider against one another along a pressing direction. A clamped area of the chain guard ring is clamped in a clamping zone between at least one of the fasteners by which the chainring is secured to the crank spider and the crank spider or chainring and thereby secured to the crank set.

A crank set for a two-wheeler, the crank set comprising a crank with a crank spider, a chainring and a chain guard ring, the chainring being fastened to the crank spider by fastening elements, and the fastening elements pressing the chainring and the crank spider against one another along a pressing direction. A clamped area of the chain guard ring is clamped in a clamping zone between at least one of the fasteners by which the chainring is secured to the crank spider and the crank spider or chainring and thereby secured to the crank set.

A guard assembly for a chain and chain ring includes a bracket and a guard. The bracket and the guard are configured to move relative to one another. The movement is governed by a resilient spring placed to absorb and release impact energy imparted to the guard.

A guard assembly for a chain and chain ring includes a bracket and a guard. The bracket and the guard are configured to move relative to one another. The movement is governed by a resilient spring placed to absorb and release impact energy imparted to the guard.

A single-sprocket system for integration into a bicycle trainer, the system including a sprocket having teeth about a perimeter of the sprocket, a first planar side, and a second planar side, wherein the teeth of the sprocket are configured to engage a chain of a bicycle mounted to the bicycle trainer. The system further includes a first chain guide adjacent the first planar side of the sprocket, wherein the first chain guide is configured to re-engage the teeth of the sprocket with the chain when the chain has become disengaged from the teeth of the sprocket towards the first planar side, and a second chain guide adjacent the second planar side of the sprocket, wherein the second chain guide is configured to re-engage the teeth of the sprocket with the chain when the chain has become disengaged from the teeth of the sprocket towards the second planar side.

A single-sprocket system for integration into a bicycle trainer, the system including a sprocket having teeth about a perimeter of the sprocket, a first planar side, and a second planar side, wherein the teeth of the sprocket are configured to engage a chain of a bicycle mounted to the bicycle trainer. The system further includes a first chain guide adjacent the first planar side of the sprocket, wherein the first chain guide is configured to re-engage the teeth of the sprocket with the chain when the chain has become disengaged from the teeth of the sprocket towards the first planar side, and a second chain guide adjacent the second planar side of the sprocket, wherein the second chain guide is configured to re-engage the teeth of the sprocket with the chain when the chain has become disengaged from the teeth of the sprocket towards the second planar side.