Sprocket Shaft Tapered Roller Bearings

Ball and roller bearings absorb radial loads — that is, forces acting in the direction or plane of rotation. They hardly absorb any axial loads.

For decades, Harley-Davidson used roller bearings for the crankshafts of its twins and singles, while axial forces were handled by thrust washers.

From the 1930s onward, tapered roller bearings became increasingly common — patented by a certain Mr. Timken. These bearings handle both radial and axial loads, and when installed in pairs, in both directions.

When Harley-Davidson began, in the mid-1950s, to support the highly stressed left side of the crankshaft — the sprocket shaft — with a pair of tapered roller bearings, the ever-increasing engine power was much better absorbed.

These bearings came from industrial production, ready to install — just like our high-quality bearings for the sprocket shaft.