Wheel bearings are among those vital motorcycle components that are out of sight and out of mind... until something goes wrong. Wheel bearings failures can do expensive damage to your motorcycle and can result in a dangerous loss of control and a crash as well. So let’s give them some love!
Check your motorcycle’s owner’s manual for wheel bearing inspection intervals and maintenance procedures. Most motorcycles now have non-adjustable ball-bearing wheel bearings, and usually they have shields and are non-greasable. Wheel bearings often last the life of the motorcycle, but riding through deep water, on rough terrain on sandy and dusty roads, spraying the bearing areas with high-pressure washers, overloading, and failing to lubricate (if needed) can shorten their service drastically.
Follow factory recommendations when you inspect them, and replace them if any signs of looseness or wear is present.
When tires are replaced it’s a perfect time to also inspect and service wheel bearings. Using a center-stand or motorcycle jack, support the motorcycle so they weight is removed from the wheel and axle. Be sure the motorcycle is safely and securely supported so it can’t tip over or fall. Grasp the wheel and tire assembly, and try to wiggle the wheel side to side to detect any looseness in the wheel bearings. Any noticeable play may indicate a loose or worn bearing and requires further inspection.
If any metal dust, rust, or excess play is found in the wheel bearings, replacement is necessary. With the wheel off, stick a finger into the center hole of the bearing and feel how it turns by hand. It should be smooth and not be loose or stick anywhere.
Before disassembly, note how everything is positioned, including brake calipers, chain adjusters, washers, and spacers. To make reassembly easier, take photos and lay everything out in the sequence that it was on the motorcycle. On some wheels the center spacer may only go in from one side; be sure to note this. Always wear safety goggles when working with tools. If you have greaseable wheel bearings, take time before getting started to obtain some wheel bearing grease and new grease seals as needed.
Replacement is best, but sometimes you can repack used bearings with grease. If the bearings are tapered bearings or ball bearings without seals (shielded bearings), they can be easily repacked with grease. Tapered wheel bearings, typically found on older machines, can be removed, cleaned in solvent, and repacked with wheel bearings grease. If the wheel bearings are shielded on both sides, you can’t add grease, but if the bearings only have one shield on the outside, it may be possible to pack the inside with grease if it appears to need some.
If you have to remove sealed bearings for replacement, be careful not to damage the wheels and hubs. Clean the area and remove any snap rings first. There are several ways to remove and install wheel bearings. I usually find it expedient to support the hub on wooden blocks on a concrete floor and drive them out carefully with a hammer and brass drift. Make sure your drift is pressing only on the bearing and not the inside of the wheel hub casting.
Most wheel hubs are made of aluminum, so if the bearings are difficult to remove, head the hub with a hot air gun to expand it so the bearings will come out and go in more easily. Several other tools can be used to remove wheel bearings. One uses two metal hooks on fingers with a slide hammer to pull the bearing out. These methods ruin the bearings, so if you have to drive out a bearing, always replace it. Instead of driving it in with a hammer, you can make a small press out of a threaded rod, nuts, washers, and a socket to slowly press the bearing into the hub. It’s also possible to take the wheels to an automotive or motorcycle shop and have them pressed in and out with a hydraulic press. Re-install all parts in the reverse order of removal. Tighten all fasteners securely to factory-specified torque.