Will changing fork oil stop the leaking?

Yamaha FJR Motorcycle Forum

Help Support Yamaha FJR Motorcycle Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Mackeroni

Well-known member
Joined
May 4, 2008
Messages
152
Reaction score
23
Location
Canton, OH
Two years ago at 37,500 miles, the right fork on my 2008 started leaking. It created a coat of grime on the brake line, brake caliper, pads and wheel. I got the SealMate and it worked great.

Then last year, after riding only about 500 miles, it started leaking again. I used the Seal Mate again, and again I was happy with the results. Now I am wondering...why did the leak start back up again after only 500 miles? Is it possible that my fork oil is so contaminated that pieces of crud migrated up into the seal to cause the second leak? And if this is true, if I flush and fill my forks with new oil, will I be safe from future leaks? I want this problem to go away, but I am not equipped to rebuild my own forks, nor do I trust the local hack mechanics to do it for me.

All comments welcome.

 
I used to mix about 30cc of transmission sealer in with new fork oil and it was a fairly effective way to stop minor fork leaks but it was only a temporary fix. if the Seal Mate doesn't work then you probably need new seals.

 
Now I am wondering...why did the leak start back up again after only 500 miles? Is it possible that my fork oil is so contaminated that pieces of crud migrated up into the seal to cause the second leak?
The reason the seal starts leaking to begin with is that the seal lips get contaminated with road spooge and bug guts that get plastered on the inner fork legs, and then works its way down under the dust seal to the oil seal. You may not be aware, but the oil seals actually have a double lip.

If after cleaning the seal it is dry, even for just a short time, that's good as it tells you that the seal is not damaged. You really need to make sure the seal mate slips under both of the lips when cleaning to get all the spooge out. You also want to diligently clean the upper part of the seal that you can get at (Q-tips are your friend) the inside of the dust seal, and the inner fork legs.

I seriously doubt that the small amount of dirt that might get past the seal would cause too much of a problem once it has fallen into the large quantity of fork oil inside the fork leg. More likely you just aren't getting all the spooge out of the seal.

PS - FWIW - I have found I can do a much more thorough job of cleaning the seals with the fork legs off the bike vs when still mounted on the bike. Of course that isn't always practical, like on the side of the road in BFE.

 
Last edited by a moderator:
Fred is probably got the right answer. If you do decide to change the fork oil, since you have to pull the tubes off the bike to do that you may as well replace the seals while you are there.

 
Another reason it can start to leak again or appear to start to leak again after 500 miles is that it takes a while for the fork oil to fill up the space between the oil seal and the dust seal. It then starts to reappear. The severity of the leak and how hard the suspension works will determine how long that takes. New oil isn't going to stop any leaks. If the Sealmate was used properly and it keeps leaking at those intervals, then it's time for for new seals, or better yet, new seals and bushings.

Eventually, it happens to everyone. I put rubber bellows boots on mine to eliminate the problem, or at least increase the time between service intervals.

 
Thanks guys... I appreciate the input. I will give my fork a few more passes with the SealMate and watch for leaks this summer. If it starts up again, I will bite the bullet and learn how to do the repair myself (thank God for YouTube), or send my forks and a blank check to Race Tech.

Peace... Mack

 
Doesn't hurt to change the fork oil anyway. It will be pretty grotty and particulates won't improve the sealing issue. Also much easier to do a good job with the Sealmate with the forks off the bike.

 
With the mileage you're at, the forks are overdue for a bushing and seal change. Changing the fluid and performing a seal good cleaning might delay the inevitable but you're on borrowed time.

Since you don't trust local shops, hook up with an upcoming Tech Day, order parts, bring plenty of adult beverages, make new friends and get the forks rebuilt!

--G

 
Fred is probably got the right answer. If you do decide to change the fork oil, since you have to pull the tubes off the bike to do that you may as well replace the seals while you are there.
Changing the seals usually means doing the bushings too. Changing oil is far less involved than either of those things. But on a 2nd Gen, which has the 3 bushing design, I would guess that --G is right and the bushings will have the teflon worn off of them. If it were a 1st Gen I'd leave the bushings alone. They don't seem to wear out even after much higher miles.

 
Last edited by a moderator:
You are well overdue a fork oil change when getting on for 40000 miles, I know Yamaha don't list it as a service item, but my fork oil is changed at every 2nd front tyre change, about 16000 miles, and to be honest, if I wasn't such a lazy SOB, it would be done every 10000 miles. The difference is noticeable. My forks were upgraded at 30000 miles by Maxton, here in UK, and required two new bushes and the seals were replaced although they hadn't failed, and I intend to change the fork oil in future at every front tyre change. I know it is a PITA doing a fork oil change, why Yamaha couldn't have made the forks with a drain plug puzzles me, because the fork oil that has a service life of 10000 miles without degradation has yet to be produced.

One other thing, I have searched for, but been unable to find, fork gaiters to fit an fjr, I realise gaiters are not fashionable but when fitted, fork seals will last forever,..., well, nowt lasts forever, but they will last a whole lot longer.

 
Most likely you could have debris trapped within the dust seal scratching the fork legs.

Depending how deep they are,they can be polished out with Autosol.

Pop the dust seal and have a look, or better still take the forks off and inspect.

Only takes a few hours to change out the seals.

BUT NO, changing fork oil will NOT stop the leaking

 
Thanks guys... I appreciate the input. I will give my fork a few more passes with the SealMate and watch for leaks this summer. If it starts up again, I will bite the bullet and learn how to do the repair myself (thank God for YouTube), or send my forks and a blank check to Race Tech.
Peace... Mack
I'm new to the FJR, but my previous bike was a 1999 Yamaha XV1100.

I read a few repair manuals, watched a few YouTube videos, then ordered up factory Yamaha seals & fork oil.

Truth be told, everything went quite well and I was really happy with the results.

I tend to overthink everything and basically need both the manuals AND the videos.

For me, things really don't become clear until I start to tear into it.

Then it all seems to make sense.

You can do it! :)

 
Last edited by a moderator:
Top