Filling Forks

Just read the thread on changing fork oil but did'nt see the info I'm needing. I'm sure this is a silly question but I have never messed with forks. Anyway, changed the motor oil this evening preparing for a HS on Sunday and noticed I have a seal leaking. I don't have time to get it to my mechanic before the race so was wondering can I add oil through the air bleed screw or do I need to remove the top cap? I just want to get through the race, I hate to miss this one but I don't want to ruin the fork bushings either. By the way, second bad seal with only 350 miles on this bike...sheesh! Either crummy seals or just my big fat keester!

Yes you can fill through the bleed hole. Trick will be getting it to the right height. Do a search in the forums on seals and the tricks to keep them sealing.


You should fix it, it's normally only a 20 min job and it's only Thursday.

Do you have Showa or KYB, I can walk you through it if you want, send me a PM.

the only correct way to measure oil height is to remove the fork cap. to put too much oil in would be worse than a bit short. i don't think the seals are any worse than anybody elses. it's more how we take care of them. don't blast the seal area of your fork when you wash the bike. it forces dirt where it shouldn't go. if there is dried mud on your tubes from your last ride, clean them before you ride again. get a piece of film negative, trim off the notches on the side, and slide it up between the tube and seal/wiper. as you slide around the tube, slide out a few times. this should get out most of the dirt that is causing the leak. don't over look the seal saver product.

Thanks to all for the quick replies and advice. Moto9 due to work schedule I won't be able to pick up new seals before Sunday, I would however like to hear your method of replacing. Looks like I need to learn it myself if I'm going to replace them every 150 miles or so. I don't use a pressure washer but do wash after every muddy ride. I will also try the film cleaning trick mtrablue.

You'll be suprised how easily you can check the fork oil level, and you'll be very disappointed in the performance of the forks in the next race if you don't have the oil levels properly set.

Just make sure you have a thin 17mm open end wrench to remove the fork rod from the tube cap. Also, I supported my bike with a hydraulic floor jack so I could raise and lower the bike. The rest is pretty easy and will take lest than an hour. After that you will have an idea of the work necessary to change the fork seals and you might what to try that next.

Try running a good quality business card undenieth the fork seal and all the way around. Try to angle it so as to pull any debris downward. This is an easy way of cleaning the seals. Works for me and a lot easier than seal replacement. You may have to replace them but this is worth a try.

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