How do I change my Fork Oil, seals, etc?

Anyone out there done their own oil change? I never have and would like to have some input before I tear these down and do them. I have the shop manual as well as the owner's manual and am a good mechanic. Just looking for some tips and time saver advice.

The reason I'm doing it is that after a day of riding, I noticed a small ring of oil on the fork tube after I unload the bike. I wipe it off and compress the forks a bit and a smaller ring appears. There is no drastic dripping or gushing going on. But I don't want to neglect this.

The up side is I can always take the forks off the 02 and put them on the 03 till the 03 forks are done. Two bikes - what a way to go!

The manuals do a great job covering this topic. My only advice is to use soft jaws in your vice and invest in a seal driver. The driver make putting things back together VERY easy.

What the heck is the deal with these seals anyway... I just noticed the other day that I am leaking oil out of the right fork too? I have maybe 20 hours on the bike, and I use a 2x4 in between the tire and fender when I tie it down. Heaven only knows it shouldn't be from jumping, since 3 feet shouldn't hurt anything. :)

Do a search on Front forks "Oil Change" This should help. Also you can use a pvc pipe with a slit in it as a fork seal driver and a 1x6 board with a groove cut out to the same inner dimensions as the mechanics stopper tool. No need to make changing seals and oil expensive. Also, you should polish the inner cartridge rod with a scotch bright followed by some metal polish. This helps "big time" for less stiction.

listen to antman believe me he knows.

do the search and also try the picture negative trick on the seals. you should figure it all out in the search.

You can do it. You only need the cap wrench. The other tools can be made cheaply. Below is a post I did for the mechanics stopper tool (you need this). Also, you can use a pvc pipe with a slit in it to drive the seals and outer bushing in. I used the inner roll (hard cardboard) of some drywall tape(home depot) with a slit (saving 70.00). Note their orientation and use a piece of saran wrap or a baggy as a condom to slip the seals over as the sharp edge of the fork tube as you can destroy the new seals if you don't. I would use the Race Tech video if you have never done this before. It covers all of this in detail.

Prior Post:

I actually made mine out of a 1X6 board that is abut 1.5 feet long. I just cut the U shape out with a jig saw. You will need a vice with soft jaws (or a leather strap like I use) as well. You drain the oil out of the top(big brass colored nut), which is the cartridge. This is actually the only part I needed a special tool for. You can get it from Then temporarily screw the cartridge top back in hand tight. Put the bottom of the fork where the axle pinch bolts are in the vice. Loosen the center bolt on the bottom. Once the center bolt on the bottom is loose you push the top of the fork to compress the spring and the catridge rod comes out the bottom. You have to press it far enough that you can slip the mechanics tool behind the lock nut. Be sure to turn the rebound adjuster fully clockwise before loosening the center bolt or you can screw up the aluminum push rod that adjusts your rebound damping. Hold the lock nut with a wrench and loosen the center bolt. Stop turning about half way and turn the rebound adjust fully clockwise again and then take center bolt completely off. Compress the top of the fork to remove your mechanic tool. Unscrew the cartidge and pull it out. Now your spring comes right out. Installation is reverse. I wouldn't worry about replacing the cartridge oil just yet unless your bike has a lot of hours or you are changing oil types. Mine was very clean. The cartridge has its own oil and it is seperate from the main fork oil. The instructions in the manual cover this pretty well except the part about the rebound adjuster that I added above. When you are installing the center nut, be sure and turn your rebound damping all the way counterclockwise once you start feeling resistance by hand and then tighten center bolt to spec.

you can use a 15 mm box end wrench as the stopper tool.

you can also do this without a vise like this.

break the 22 loose at the bottom of the forks while they are on the bike.

remove forks, oops i did use a vise for this part.

put tube in vise, break 50mm loose

drain oil

thread the 50 back in

turn fork upside down putting what is the top (50mm)on the shop floor

push the slider down, the dampner rod slides out quite easily since you have leverage

slide the 15 behind the nut assembly on the dampner rod, this will hold the dampner rod out of the tube so you can break it loose from the end cap with both hands, and a 22 and 17 of course.

this way worked pretty well for me, i was doing this job in a vice and using a tie down to hold the dampner tool out.

that woked too but its not that easy to compress you spring enough so the dampner rod slides out when the tube is in a vice. you can of course, but doing it upside down and on the ground gives mucho leverage. give it a shot

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