Fork Rebuild

Note: Special Tool May be required for breaking open the dampening rods.

I didn’t notice the blown seals and shotty fork operation on the test ride, so rebuilding the fork on this ride was one of the first things in order. Due to the requried special tool, I put it off longer than needed, here’s the pics/walkthrough.

I used the Haynes manual as a guide. When installing the bushings and oil seals, I used PVC pipe as a bushing press. I cut one shorter piece to use as a set, and a longer piece to use as a slide hammer.

First, get the front end of the bike up. I was able to do this with a couple jackstands. Take the front wheel and fork tubes out. Now you can remove the top cap and spring/spacer and drain the oil. My oil was very dark grey, and looked nothing like the fresh red liquid that was used as replacement. Notice I put the fork in a vice with some rubber cushoning (camper shell sealer) on the vice jaws. Also keep in mind the top cap is under a bit of spring tension, so be prepped to catch the cap and start draining the oil.

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Once the oil was drained I tried to get the tubes apart, but it requries a special tool to hold the dampening rod. You can see the 12 sided recess that the special tool fits in to keep the tube from spinning.

Here is a picture looking down the fork tube with the oil drained.

This is a close up of the same picture above, you can see the 12 sided recess in the top of the dampening rod.

I could not get them apart so I took them to a local shop to get them broken apart. The guys at the shop used and impact wrench and I belive they did not have to use the special tool to get them apart. In any case, here's what I got back from the shop

Here is a shot of the old fork seals(in bottom of pic). You can see how bad they are. In order on the tube from left to right, is the tube bushing, back up ring, oil seal, and dust seal. *Note that there is a stopper ring that normally goes between the oil and dust seals, but in my case due to the rusting, mine were disentigrated and rusted into peices.*

While I had this out, I made version of the special tool out of an oak dowel to help with reassembly.

Also in the top of the picture are the two plastic oil stoppers that go on the bottom of the dampening rods. On reassembly, make sure you pit them on the same way they came off (tapered side facing up). Here is a better picture of the dampening rod and recess that requires the special tool

Here you can see debris in the fork leg. There is a recess that the snap ring slides into that must be free of debris. I used some degreaser/toothbrush/paperclip to get it back to spec.

Here is the snapring, new in package. It goes between the oil and dust seal.

Once the lowers were cleaned up I reassembled the tube (reattach the dampening rod to the fork leg and tube, then put in the springs, spacer and oil). Since I did not have an impact wrench and my specail tool might not hold up to hight torque specs, I used some non permanent locktight to seal the bolt on the bottom of the fork leg (as the manual suggests). Now the tubes in the legs will help guide the bushing and bushing driver, and oil seals and lock rings Here is the leg with the bushing, oil seal and lockring in (only missing dust seal). Look closely and you can see the lockring on the right side

After that it is just the dust seal (I pressed mine in my hand) and reinstall the tubes on the bike.

My results were much better than compared to the old fork. I think my seals were not only shot, but the fork was really low on oil, so having oil dampening in the shocks really helped a lot.