Patent ID: 8882619

Claim:
A sprocket engageable with a chain having successive alternating pairs of inner link plates and outer link plates connected by pins, the pins encased by rollers, the sprocket comprising: a plurality of sprocket teeth on the outer periphery of the sprocket, each of the teeth having a tip and a root, a load flank for contacting the chain, a non-load flank, and a first side and a second side opposite the first side; a first tooth of the plurality of teeth including a recess formed on the first side of the first tooth; and a second tooth and a third tooth of the plurality of teeth sequentially adjacent to and preceding the first tooth in a non-drive direction of the sprocket, each of the second tooth and the third tooth having a notch on the second side for providing space for the chain when shifted from a smaller adjacent sprocket onto the sprocket for the purpose of gear shifting and for providing contact areas for contact with the inner and outer link plates of the chain; wherein the recess extends one or both of to the tooth tip and to the non-load flank of the first tooth, but not to the load flank of the first tooth, and includes a recess base configured to contact and support an outer link plate of the chain, wherein the recess is configured to receive a portion of the outer link plate and extends at least along the first side of a fourth tooth of the plurality of teeth adjacent to the first tooth in a drive direction of the sprocket.