Before getting started with reinstalling the front wheel, and while the front wheel is off of the motorcycle, be sure that you check the front wheel bearings to ensure they turn smoothly, and that there is no play in the bearings, as this can be done by removing any external spacers and inserting your finger into the inner race and turning the bearing. If any roughness or play in the bearings is felt be sure you replace the wheel bearings before re-installation of the front wheel.
Once everything such as the front wheel bearings look and feel good, (or they've been replaced) apply a light coating of waterproof grease to the outer spacer(s) where they contact the outer hub seals and reinstall the spacer(s) to the hub, then apply a light coating of grease to the front axle and let's get this party started.
- If you are working on a motorcycle with forks that have removable axle pinch blocks and the pinch blocks were removed, be sure that the blocks are checked for any indicators that denote "Up", then reinstall the pinch blocks to the fork leg with the nuts that clamp these blocks loosely installed before continuing.
- If working on a motorcycle that has through bolts which clamp the axle, it's a good idea to remove these bolts and apply a coating of anti-seize to the threads before continuing.
- Once the front wheel is between the fork legs and the brake rotor is correctly positioned between the brake pads, insert the axle through the pinch blocks or fork lugs and through the center of the wheel, followed with installing the nut on the end of the axle.
- Once the front wheel is in place, go ahead and torque the axle nut to the proper torque specification, as can be found in a factory service manual specific to the motorcycle you're working on.
If you have trouble tightening the axle nut...
When tightening the front axle nut, on motorcycles where the axle end is flush with the bottom of the fork leg / lug, you're supposed to have a special hex shaped axle holding tool to keep the axle from turning, although if an axle holding tool is not immediately available, you can temporarily tighten the axle pinch bolts opposite of the side you are tightening to hold the axle from turning, although this should only be done in an emergency type of situation such as during a ride or if a holding tool is simply not immediately available.
If Working without an Axle Holding Tool, Always Loosen The Axle Pinch Bolts Immediately After Tightening of the Axle Nut.
- After the front axle has been torqued to the specification found in a factory service manual specific to the motorcycle you're working on, it's important to bring the brake pads back into contact with the brake rotor and build up brake pressure at the brake lever, although if you don't have the greatest feeling brakes, be sure to check out the article on bleeding the brakes before the next ride.
- Once adequate brake pressure has been achieved at the lever, the next step in installing a front wheel on a dirt bike is to spin the front wheel and quickly grab the front brake, abruptly and momentarily stopping the front wheel while elevated, then repeat this process several times, as this will help to align the forks parallel.
- After you've spun the wheel and stopped it abruptly several times, let off the brakes and tighten the LEFT side axle pinch bolts (or nuts) to the torque specification that can be found in a factory service manual specific to the motorcycle you're working on.
- After you've tightened the left axle pinch bolts (or nuts) to the proper torque specification, spin the front wheel again, then quickly grab a handful of front brake several times.
- After releasing the brakes this time, tighten the RIGHT side axle pinch bolts or nuts to the torque specification that can be found in a factory service manual specific to the motorcycle you're working on.
Finally, check or set the tire pressure and get that thing off the stand as that's all there is to installing a front wheel on a dirt bike in a way that will ensure minimal fork stiction and allow optimum fork performance.