Abstract: A tread pattern having at least one circumferential groove and transverse grooves extending from the circumferential groove defining tread blocks there between. The tread blocks include sidewalls limiting the longitudinal groove laterally and projections projecting from the sidewalls into the circumferential groove. The width of each of the projections is less than 10% the circumferential dimension of the respective tread block. To convert a mold having elements that produce tread blocks with substantially flat sidewalls into a mold that produces the tread pattern, channels are machines into the sidewalls of the mold elements.