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2010 KTM 250 SX-F Front Fork Issues?

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Wondering if anybody else has has the same problem as me and what have you done to fix it? I am having lots of trouble getting my bikes front fork to ride smoothly over smaller rollers and desert type terrain. I have tried changing rebound and dampening and the bike possibly has softer springs but i haven not removed the caps yet. I have ridden my buddies Kawasaki and his bike doesn't punish you nearly as bad. One tip I have yet to try that I have seen, is that people have been removing 15ml of fluid out of the fork and I guess that helps the problem. I am more looking to eliminate the problem and hopefully somebody on here has had these issues and can share what they have done to fix it.

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I have found that lowering the nitrogen pressure to 10psi or so helps significantly on these WP forks.  Much more so than any amount of oil you can remove which to me doesn't make a big difference.  You may have to up the compression clickers and/or valving to compensate for bottoming, but it does really help.  For all off road riding/racing I run 10psi on my 505, and when I go to the MX track I bump the pressure up to 15psi.

 

This obviously isn't that easy to do if you don't have a needle setup to change the pressure in the bladders.

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The forks are probably not built for your riding weight and capability. They need someone to go through them and build them up.

I've had nothing but problems lowering the bladder pressure. There is too much cavitation and the fork can on accident blow through the stroke. Its an emergency fix, its not a permanent solution.

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I have found that lowering the nitrogen pressure to 10psi or so helps significantly on these WP forks.  Much more so than any amount of oil you can remove which to me doesn't make a big difference.  You may have to up the compression clickers and/or valving to compensate for bottoming, but it does really help.  For all off road riding/racing I run 10psi on my 505, and when I go to the MX track I bump the pressure up to 15psi.

 

This obviously isn't that easy to do if you don't have a needle setup to change the pressure in the bladders.

 

Dropping the bladder px to 10psi is not a good idea on these forks. The cartridge/bladder system on these forks is designed to operate with a certain px window. Running a pressure too much lower than the inteded oem spec of 1.2bar will allow excess oil to enter the cartridge via the lower rod seal from the outer chamber when the fork compresses, eventually overfilling the cartridge with oil and collapsing the bladder. It will also allow too much of your outer fork oil volume to enter the cart, possibly to a point where you could experience alot more bottoming situations and metal to metal bottom out contact (if your a fast rider, riding terrain that causes large fork stroke useage).

It would me a much better idea to get the fork serviced, correct springs fitted and valved/setup for the ridder/terrain.

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