For those of you who need to change your fork seals and do not want to pay the stealership (my local shop wanted to charge me $150 with them off the bike and me supplying the materials to complete the job...I'm too stubborn and broke for that), here you go.
If your forks are leaking you may have dust/dirt build up allowing the oil to escape on travel. You may not need to change the seals but rather clean out he debris. You can do this by simply using 35mm film (good luck finding some laying around in the digital age). Use the film like you would flossing your teeth (tooth for those of you in Arkansas, no offense Raymo) between the fork tube and the seal. Noobs, you will want to pull the dust cover up first...that is not the fork seal. I highly recommend spending $20 and purchasing some fork boots for extra protection (http://www.jpcycles.com/product/2300335
Tools and Materials you will/may need:
- 8mm allen wrench
- 24mm allen socket with every extension you can find, apx. 18".
- Flat Head Screw Driver
- If you do not have a 24mm allen socket - 16mm (24mm outside)bolt or nut (welded to the end of a steel rod)
- Turkey Baster or Spray bottle top
- 1 1/2" PVC - approximately 2'
- Fork Seals
- Fork Oil
- Depending on mileage or desired ride you may want to purchase progressive springs.
Will be doing a full write up as I finish, but to start it off, here is the tool that I had to make.
Making the Piston Tool
The size of the top of the piston head is 24mm if you had an allen head socket with a few extensions to reach down into the tube. Not having that you can make your own by going to the hardware store and purchasing a 16mm nut or bolt (nuts and bolts are measured by the shaft size, not the head size).
Weld it to the end of a rod and tada, you have a tool to tear the forks apart.
After you have the tools you need...
STEP 1 (Dis-assembly)
Remove the wheel...(duh) then loosen the top and bottom pinch bolts from the top and bottom tree. Remove the fork tube cap (Item 1 in diagram) and empty the fork oil from the fork. While pouring the oil out you will want to catch the Spacer (18), Spring Seat (17). Fork Spring (16) and Piston Ring (15).
Using the 8mm allen on the Socket Bolt (10) and your 24mm allen head with extensions or newly make fork took hold the Piston (14) and remove the Socket Bolt (10). This will allow you to start the dis-assembly of the fork tube.
Remove the Dust Seal (2). Remove the Stop Ring (3) with a flat head screw driver.
Now pull the Fork Tube (8) out of the Fork Slider (7) with minimal pressure. What you are trying to do is unseat the Oil Seal (4) and the Slider Bushing (6) from the top of the Slider Tube (7). Once this is done the fork tube will come out. You can now inspect the rest of the inside of the fork tube including the Fork Tube Bushing (11) and the Oil Lock Piece (12), these will most likely not need to be replaced.
It is a good idea to use this opportunity to clean any debris or corrosion from all parts as well as clean the top of the Fork Slider.
Generally the only parts needed to be replace will be the Oil Seal (4) and possibly the Fork Spring (16) if you want to adjust your front suspension. You can also lower your ride by changing or adding to the Spacer (18).
STEP 2 (Re-assembly)
Replace all the parts as to the diagram back into the Fork Slider (7) and replace your Oil Seal (4). You do not need to replace parts 15-18 before you refill the oil level. You will need to use the 2" PVC to seat the Slider Bushing (6) and the Oil Seal (4).
Once the Oil Seals are completely seated you can replace the Stop Ring.
This should go without saying, but make sure that the Stop Ring is completely seated in the groove on the Fork Slider.
Use your Fork Tool or 24mm allen and 8mm allen to lock the Fork Tube (8) and Fork Slider (7) back together (see manual for proper torque or use the German torque specs, goodentight).
STEP 3 (Refilling Oil)
You can determine what specification fork oil you would prefer for what type ride you desire. Once you have your oil the proper procedure for refilling the oil is to start with the fork fully compressed and fill to 4.4 in from the top.
The easiest way I know to get to this level is to use the turkey baster or spray bottle top and measure 4.4" down. This will allow you to either suck up the fluid with the turkey baster or spray out the over filled oil to the proper level.
Replace the Fork Tube Cap (1) and reassemble the forks to the tree and wheel to the forks.