How to Change Fork Seals on a Harley
Harley-Davidson motorcycles are equipped with telescopic front forks. Operating as large shock absorbers, the front forks enable the front wheel to maintain contact with the road under varying conditions. The dampening action of the front forks also protects the rider from harsh road conditions, and provides a smooth and comfortable ride. A front fork seal that is leaking reduces the dampening ability of the front fork, and may cause handling and braking problems.
- Moderately Easy
- Motorcycle jack
- Socket set
- Combination wrench set
- Drain pan
- Lock-ring pliers
- Dull flat-tip screwdriver
- Oil seal
- Fork oil
- Graduated measuring cup
- Torque wrench
Lift the motorcycle using a motorcycle jack until the front wheel clears the ground. Ensure the motorcycle is securely tied down to the jack.
Remove the brake clevis pin at the brake lever, brake shoe anchor and centering bolt on motorcycles built before 1972. Remove the axle nut, fork slider cap nuts, speedometer cable and brake caliper on motorcycles built from 1973 on.
Push the axle out of the wheel using a hammer and drift. Remove the wheel from the front fork assembly, making sure not to lose any spacers from the wheel hub.
Remove the fork tube cap. The cap is under mild spring tension; use caution when removing the cap. Use the correct size socket on the cap to prevent damage to the nut.
Place a drain pan under the forks, and remove the fork slider lower bolt. Pull the fork tube out of the slider, and allow the fork oil to drain. The slider bolt is located at the bottom of the fork tube inside the axle saddle. Some models are equipped with a fork oil drain plug on the side of the slider tube near the axle. Discard the used fork oil in accordance with local disposal laws.
Remove the oil seal lock-ring using lock-ring pliers. Pry the oil seal out of the fork slider using a dull flat-tip screwdriver. Use caution that the inner and outer surface of the slider is not damaged when the seal is removed. Inspect the fork tube, fork slider tube and wheel assembly for damage. Repair or replace any damaged or worn-out parts as required.
Grease the outside of the new oil seal, and push the seal into the fork slider. Use a socket of the same size as the seal to help push it into the slider until it seats at the bottom of the seal well. Replace the oil seal lock-ring, and ensure it has snapped completely into the ring groove.
Slide the fork slider onto the fork tube, and fasten the original screw and washer. Tighten the fork slider screw to 11 ft-lbs.
Fill the fork tube with the correct amount and type of fork oil. Consult the manufacturer's specifications for specific information on your model of motorcycle. Pour the measured oil from a graduated measuring cup into the top of the fork tube with a funnel. Tighten the fork tube cap to 11 ft-lbs. using the correct size socket.
Reinstall the front wheel onto the fork sliders Push the front axle through the sliders and wheel hub, making sure that any spacers are reinstalled in the correct locations. Replace the brake clevis pin at the brake lever, the brake shoe anchor and centering bolt on motorcycles built before 1972. Replace the axle nuts, fork slider cap nuts, speedometer cable and brake caliper on motorcycles built from 1973 on. Tighten the axle nuts to 50 ft-lbs.