*Required Tools: Seal puller or flat-head screwdriver (poor man’s seal puller), scribe or small screwdriver, 10mm and 12mm box-end wrenches, ratchet and socket set for rear wheel removal (this can vary depending on your bike's manufacturer), and rubber mallet (optional).
When was the last time you packed your rear hub bearings full of fresh grease? If you’re like most of us, you probably don’t remember. But the fact of the matter is that your bike, from the day you wheeled her off the showroom floor to every half dozen or so rides thereafter, needs it. That’s right, folks… New bikes need it. Used bikes need it. Heck, even Japanese motocross journalists' bikes need it… Bad!
Our good pal/Nick Wey’s factory wrench/aspiring Playgirl model, “Bad” Billy Felts, was happy to help us out with this month’s Race Shop, but one small problem stood in our way. His bike, Wey’s factory RM250, was already in the Suzuki semi and on its way to Dallas for round 14 of Supercross. “No problem,” we told Billy. “Swap’s RM250 is clean, sitting in his garage, and ready to go. Shoot, it even has those trick factory-looking gold rims on it!” And just like that, it was on! We all gathered in the shop while Billy pulled Swap’s rear wheel off to walk us through the steps, and woe were we at what we found. Not only were his bearings dirty and showing little presence of grease, but they were actually frozen to the strength of the human hand and unable to turn freely. Shame on you, Swap!
As Billy was quick to point out, however, bikes with some mileage on them are not the only ones you need to worry about. You know that dealer prep fee that got tacked onto the sale price of your last new bike? Well, trust us when we tell you, that fee rarely includes grease! New bikes are notorious for coming with very little grease, if any at all, and should always be gone through before your first ride. So whether your ride’s brand spankin’ new or has a few motos under her belt, make Billy proud by following these eight easy steps to lubed-hub glory. Take it away Billy…
STEP 1: While every step in this procedure is on the easy side as far as wrenching is concerned, the first step is probably the easiest, so don’t screw it up. Take your rear axle nut off with a 24mm wrench, or whatever your bike calls for, remove the rear axle, and pull the real wheel completely off the bike.
STEP 2: Once you have the rear wheel off you need to first remove the wheel spacers, and then using your seal puller or a flat head screwdriver, get up underneath the seal from the bottom side and pull the seal out. At this point you can inspect for any damage to the seal. If there is damage, you should be able to clearly recognize it.
STEP 3: Now that the seal’s off, grab a scribe or a small screwdriver and pop the dust seal off of the bearing’s outer surface. Again, it’s easiest to do this by approaching the seal from the inside diameter (I.D.) of the seal cover. Inspect the dust seal for any damage, and clean off all excess dirt and grease.
STEP 4: Next, wipe off the old grease and dirt on the ball bearings. Inspect to be sure that the individual bearings are in place and moving freely. Once you’re satisfied that all is well, liberally reapply waterproof grease onto the bearings with either a flux brush or your finger. Once you have it completely full of grease, usually flush to the bearings themselves, push the dust seal cover back onto the bearing, and any excess grease will squeeze out. The dust seal should pop easily into place. During this process the cover will help to push grease further into the bearing for ultimate lubrication.
STEP 5: It’s now time to press the bearing seal back into place. If you didn’t already in step two, inspect your seal to make sure it’s not torn. Also, check to make sure the spring is still around the lip of the seal, and wipe out and clean all old grease and dirt thoroughly. With your waterproof grease, apply a thin coat around the seal’s outside diameter (O.D.) to help make it slide into the hub a little more easily. To press the seal into place, start by using your thumbs. More often than not it will press in smoothly, but if needed, a small rubber mallet can be used to tap it in flush. Before you put your axle back in it’s also good to put a thin layer of grease on the I.D. of the seal as well. This will allow the axle and wheel spacers to move into place smoothly.
**Repeat steps two through five for the other side of the hub**
STEP 6: Now that the bearings are cleaned and greased and the wheel is ready to slap back on, you’ll want to take the axle and clean it with contact cleaner, getting all of the excess dirt and grease off of it.
STEP 7: Using a brush or your finger, re-apply grease to the shank of the axle as well as the threads, which will keep the nut working properly. Put your wheel back up into place, slide your axle back in, and just barely snug the axle nut for the time being.
STEP 8: At this point you can check for chain tension to see if your chain is too loose or too tight. A simple measuring guide to use is your fingers. For a normal person, a three-finger gap between your swingarm and chain, just behind the chain block, should be perfect. But for people with big sausage fingers like me, two fingers is more accurate. Use the indicators on your swingarm and your axle blocks to make sure that everything is lined up and square on both sides. Finally, before you tighten your axle, be sure to slide a towel or wrench between the chain and the sprocket in order to push the wheel and chain blocks up against the jam nuts. Other than that, spray on a little chain lube and you should be good to go.
