Quick And Dirty Twin-Chamber-Fork Seal Changes - Dr. Dirt

Slide the inner fork tube over the fork spring and damping rod.

Slip the seal and wiper up near the axle clamp. The bushing on the end of the steel tube will slide right in. The other bushing will need to be forced in. Let the spacer sit on top of it as shown.

Use a seal driver like this one from ESP (818/249-6744) to drive in the bushing. Seal drivers are available from Race Tech, Motion Pro and the bike manufacturer. It makes this job easy.

When it fully seats, the seal driver will generate a solid clack. You will hear the difference in the sound when it is in right.

After the bushing is seated, slide down the seal and start it in with your fingers. Use the seal driver to knock it all the way in. As with the bushing, when the seal seats it will produce a solid, sharp sound. Plus, when you look in the seal bore, you will see that the snap ring groove is fully exposed, so the snap ring will seat easily. Push in the snap ring with your fingers, then use light pressure from the seal driver to lightly seat the snap ring all the way around. Inspect it visually to make sure it is seated.

Use your fingers to push in the wiper. The seal driver is not shaped to drive the wiper in without damaging it. It takes a good push but will go in with just finger pressure.

Push down the fork tube and slide the special tool or a 12mm wrench under the lock nut. Thread on the base bolt. There is a rod that extends from the base of the Showa bolt, and it has one flat side. The small rod inside the cartridge rod also has one flat side. Make sure the rod is inserted into the tube correctly before you thread on the base bolt. Use a torque wrench to tighten the base bolt against the lock nut. The manual has the torque specification.

The base bolt is then torqued into the axle clamp casting. This torque figure is much greater than the torque against the lock nut. Use the axle to hold the fork while you tighten the bolt. All that is left is to put the fork legs back on the bike. Remember how you counted the rebound clicks? Set the rebound back to the number you counted before you ride. Once you do this a couple of times, a fork seal will be a 30-minute job.