Leaky fork seals Anodizing, what will help?? Frustrated!!

[MikeT]

Here is the deal. I have a 2000 YZ250 and my fork seals have been leaking pretty much every time I ride. Last fall, I completely dis-assembled the forks and replaced the dust covers, the seals, the pistons, and the bushings. I cleaned everything off and put new fork oil in. I protected the seals by putting plastic over the top of the tubes when installing them so they wouldn't get cut during installation. I added grease as indicated during installation....... They still leak!.. The lower tubes are not perfect and show some scuffing but no grooves or anything like that. I couldn't feel any sharp protrusions.... I just don't know what to do.

I saw on ProCircuit's website that they have as a suspension service where they "Hard anodize" fork tubes. Is is possible that my lower tubes, although they don't look too bad, might actually be bad enough to cause the leaks? Is this anodizing something that can help re-surface the tube and help to stop the leaks? I am about at the end of the line with this problem and do not know anything else I can do to fix it. If I buy another set of used forks they may have exactly the same problem that I have. Please give some input on this situation.

Thanks

BTW, I don't care who fixes the problem, MX-Tech can have my business if they have a solution. I just want the leaks to STOP!!!

 

[Chili]

I would box them up and send them to Jer at MX-Tech to inspect them. Give him a call let him know you are from DRN and let him know the troubles you are having and I'm sure he will get you sorted in short order once he's seen the forks.

 

[RM_guy]

It might just be some damage to the inner tubes. If you can see where, you can polish it out with some 600 grit wet/dry sandpaper. If you don’t feel comfortable doing that then don’t try.

Otherwise I'd send them to Jeremy. He can clean them up like new if there aren't any bad scratches. I just got my suspension back from him and the surface finish on the inner tubes looks great. He also now sells some new seals that have a much longer life that he claims really work. Once the snow melts I'll get to try them out.

 

[Bonehead]

This is a fix I have done for years with great results.

First take the fork seals you just put in, out
look at the inside of the seals. You will find a spring under the lip of the seal. Pop the spring out of the seal.You will see how they are put together. One end of the spring screws into the other.Twist the spring to unscrew it. You now have a straight spring. One end looks like a screw the other end is just coils on a spring. Now cut Three coils off the coil end.(I do this on the bench grinder) Now twist the spring back together pop the spring back into the seal put the seal in the forks no more leaks

 

[MikeT]

This is a fix I have done for years with great results.

Now cut Three coils off the coil end.

Is this to just put more tension on the spring?

 

[Bonehead]

Yes this makes the spring tighter and makes up for wear on fork tubes This has worked on every kind of seal from waterpump to shift shaves

 

[Chili]

He also now sells some new seals that have a much longer life that he claims really work.

Jer put those SKF seals in both our bikes last year, I was likely one of the first as they had just arrived when I stopped by MX-Tech. Besides how durable they are it's shocking how much less stiction they have on the fork tubes.

 

[whenfoxforks-ruled]

Did you measure them? It could be worn. My rear shock shaft is getting replated. With a better material, that should wear the seals less, and make the shaft true. Anodizing is for looks. MX-Tech.

 

[MikeT]

Did you measure them? It could be worn. My rear shock shaft is getting replated. With a better material, that should wear the seals less, and make the shaft true.

Who does the replating? I am going to give the sandpaper and spring trick a try but if that does not work I uess I'll have to see about the replating. Who does this?

 

[RM_guy]

... Besides how durable they are it's shocking how much less stiction they have on the fork tubes.

I haven't put them on the bike yet but I did notice less stiction when just playing with the forks. Very smooth. I'm dying to try out the new, woods only valving and put those seals to the test.

 

[Wolf]

I had the same problem as Mike...could not get the forks on my YZ to stop leaking. After 2 seal replacements I finally found out about Jer's new seals, installed them, and voila...no more leak and Chili is spot on with his observation about the stiction.

I think the seals are 50 or 60 bucks...can't remember

 

[helio lucas]

one nice trick is to put a lot of vaselin (vaslin??? not sure) on the seal prior to mounting. no kind of pun intended!
on a time where we cannot get any replacement seals for a pit bike, this trick helped the forks to hold for more than 10 races without leak with a very good rider on board. :cool:

 

[whenfoxforks-ruled]

Who does the replating? I am going to give the sandpaper and spring trick a try but if that does not work I uess I'll have to see about the replating. Who does this?

I am not for sure who Jeremy uses for re-plate.

 

[MikeT]

I have just put one of my fork legs back together. I did the spiring trick that Bonehead recommended on a brand new Yamaha seal. I also did the light sanding that RM_guy said to do. I used 800 grit sandpaper instead of 600 because I was chicken. The tube looks really nice and I just need to ride it to see if all of this worked. I pushed up and down a lot with the tube and it didn't leak but riding it will be a different story.

 

[Bonehead]

Mike did your forks stop leaking or not ?

 

[EncyclopediaRonnie]

were they genuine seals? ive had alotta trouble with generic seals not being to corect size and leaking. up to almost 3mm differnce once. not on forks tho

 

[whenfoxforks-ruled]

Genuine? MXTech is using some new green after market seals, so far so good, again!

 

[OldTimer]

...I pushed up and down a lot with the tube and it didn't leak but riding it will be a different story.

How 'bout a guy who cranks up a thread like this and then leaves us hangin'.
I just rebuilt the forks on my son's '06 YZ for the third time in about five rides. Well... seals the first two times, rebuild kit this time with bushings and o-rings and all.
Not sure what to do if they leak this time. Maybe I'll just put half a quart of 5w through the bleeder hole before each ride. Kinda like the way I added oil to my pickup truck in high school. ;)

 

[OldTimer]

Well...
Two rides later and the right tube is hemorrhaging.
A guy suggested 1600 grit sandpaper followed by Mother's Polish on the stanchions.
I guess I'll try that and then leave ya'll hangin'.

 

[RM_guy]

Well...
Two rides later and the right tube is hemorrhaging.
A guy suggested 1600 grit sandpaper followed by Mother's Polish on the stanchions.
I guess I'll try that and then leave ya'll hangin'.

That will make the surface too smooth and the seals won't get any oil. There has to be some roughness on the inner tube to retain oil that lubes the seals. Use 600 grit.

 

[dirt bike dave]

OldTimer - have you tried the spring trick Bonehead described above? I've never used it myself, but have heard about it many times from 'old timers' who have been maintaining bikes for 40+ years. Apparently it works pretty well.