There have been many changes in the wheel bearings that Harley has used over the years. They've used ball bearings, roller bearings, and the factory has recently switched over to a dual-row ball bearing design that is double-sealed to keep out dirt and moisture.
Wheel bearing maintenance is of vital importance, since poorly serviced bearings can bring your bike to a crawl, or even worse, they have the potential to completely lock-up a wheel and cause injury.
We dropped in on our friends at Wheel Works in Garden Grove, California, to check out the differences between the early and late bearings used by Harley-Davidson. Gary at Wheel Works also took a few minutes to explain what to look for when servicing tapered roller bearings and the proper way to clean and repack them with fresh grease.
Even though most recommendations point to cleaning and servicing roller bearings every 10,000 miles or so, Gary makes a point of inspecting bearings at each tire change to ensure his customers are on the safe side.