Rivera Pro-Clutch

The clutches of Knuckleheads, Panheads and Shovelheads originally use ten strong coil springs. With a foot clutch or a “Mouse Trap” this is no problem — but with the hand clutch, which became standard on Harley-Davidson models from 1965 onwards, things are different. Harley did offer weaker clutch springs and an additional pair of plates for this configuration, but adjusting the springs properly was still tricky.

The Pro-Clutch replaces the ten coil springs with a diaphragm spring, similar to those used on Evo models. When correctly adjusted, it even provides a self-energizing effect: once you pull the clutch lever past a certain point, the pull becomes progressively lighter. Thanks to the more than 50% larger friction surface, the same power is transmitted with less spring pressure. As a result, the Pro-Clutch requires less hand force to operate.

In addition, the Pro-Clutch features a double-row ball bearing with seals on both sides to guide the clutch basket. Spring preload is adjusted by evenly tightening four nuts — no distance measures, no indexing of nut faces into notches. Just simple and easy.

The kits fit inside the original clutch basket and require no more space than the old 10-spring clutches. They also fit inside the stock primary chaincase, and installation is no more complicated than that of an original clutch.

Each Pro-Clutch kit includes a clutch hub with bearing, friction and steel plates, a pressure plate, a diaphragm spring with retainer plate, four spring adjustment nuts, a clutch hub nut with seal, and English installation instructions.