Ktm Forks Sticking

I just replaced my fork seals on my 2008 450xcf 48mm forks with moose racing fork seals. Got it all together and noticed that when I compress the forks with the front brake, the forks go down and just stick like I have them locked in with a holeshot kit. I does this but sometimes it won't stick. I put everything back in the same way it came out. I went on a ride yesterday, hit jumps and the forks seemed to be fine, no sticking. I also noticed something weird when I pulled apart the forks. The left side contained no plastic shims while the right side fork ( non disc side) had two plastic shims on top of the spring and one below on the valve side. Seems a little odd to me, what do you guys think?

As for shims, That is to get proper preload on the spring. It sounds like maybe one sprintg was sacked a bit and got shims to preload it correctly and the other spring is alright. I would measure both ,total length, and replace if nec. As far as sticky seals, I pollish my tubes and coat them with KYB suspension grease to lube them( or petroleum jelly such as Vasoline works too), I have never seen a seal cause a fork to stick though, maybe something else is goin on there. I would double check the fork assembly, since it is a poss cause of injury.

the triple lip seals are well known for stiction

It's most likely the seals, since 2010 KTM has used a seal made from a slicker material and back to a double lip seal.

The 2011 & 2012 have almost no stiction.

Should have read the post...those seals suck. But check the axle anyway. Noticed he has updated his procedure...as he mentions "perfectly centered" isn't always the free'est moving...

ried the re centering the axle with keeping the non brake side loose, thought I made it centered but that didn't fix my problem. Made it a little less stiction, but the forks still stick down mid to half way down the stroke. I am going to lube up the fork legs and see what that does. I bought Moose seals and they shouldn't be having this problem. Maybe the lube will do the trick?

The Moose seals are junk. You will NOT get them to move freely. Only took me once to find that out...

After you check the alignment, read this thread:


I've heard the same issue about KTM seals and the benefits of the SKF brand. I just dropped off my forks to the local tuner tonight for a revalve along with a set of new SKF seals and wipers. We shall see.

When I took the forks apart to change the springs on my 2011 300 XC, I noticed one fork had more preload shims in it than the other. When the factory assembled the forks, the springs were probably a little uneven so they made up the difference with unequal shims. Those shims are about $25 a piece which is ridiculous. You can use 1-1/4" schedule 40 PVC pipe instead for a WHOLE lot cheaper. That's what I used to make the shims match on mine and it worked beautifully. I cut the pipe into shims using a band saw. Whatever you cut them with, make sure they are cut square (not literally square, I guess flat would be a better word). Measure everything with a digital caliper. Hope this helps.

Resolved my problem. Took off the front wheel, lubed up the fork tubes with Vaseline, Spun the forks around and re-tightened them. Now no more stiction, I think It was a combo of lack up lube, forks maybe were too tightened and the wheel needed alignment. Now time to throw some fresh tires on and hit up Glen Helen!

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