Since the mid 1970es the name PBI stands for high quality sprockets. After precise manufacturing the transmission sprockets are electroless nickel-plated against corrosion. Electroless plating provides a uniform deposit thickness, disregarding the shape of the plated object.

These transmission sprockets are made for narrow 520 chains (5/8” x 1/4” pitch) and fit 5 speed Sportsters 1991 and up. Their object is to realize somewhat wider tires with as little drive train offset as possible. Sports oriented riders like the narrow chains for their lower rolling resistance.