Abstract: A self-cleaning sprocket, especially for use with an endless belt having internal drive lugs in a crop gathering unit, being a body of material having a disk-like base portion and a plurality of radial ribs extending axially from the base portion and converging to a central hub portion, the ribs and base center portion defining a plurality of open-ended lug-receiving pockets. The portion of the base portion in the pockets slopes axially toward the open end from the periphery to the hub portion and the hub portion slopes radially inwardly from the base portion to the open end, the intersection of the hub and base portions being filletted to promote the flow of debris from the base portion to the hub portion. The axial end of the sprocket is preferably flat and without obstructions and extends beyond the lateral edge of the belt. The sprocket is preferably mounted with the pockets in a generally upright position from its opposite axial end whereat a second plurality of pockets are formed.