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350sxf front fork problem

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hey guys im literally all out of ideas the problem im having is the front feels very loose for example im understeering but not due to rebound to slow or fork height its because when i go to turn in it has a strange washy/knify feeling

my sag numbers are in check rear 35mm/107mm (sand track) ive tried moving the forks up and down ect with no help.. ive even had it revalved a 2nd time just to make sure it wasnt the valving.. both tuners are what all the fast guys are using so definetly not valving.

When u sit/bounce on the bike the forks have a dry sticky feeling not nice and smooth, even tried crc the fork tubes with no help... if anyways has some ideas or input im all ears thanks

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What year?

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2012 so springs are correct according to race tech site as the new valving is race tech gold valves

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You using skf seals and decent bushes? How old are the bushes?

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i just put the bike in the shop today to do seals and check bushes and change if so be it.. ive played around with the clickers but no help to my problem i havnt strayed more then2-3 clicks then what my racetech sheet says.

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oh the seals and bushes would be around 50 hours id say

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i just put the bike in the shop today to do seals and check bushes and change if so be it.. ive played around with the clickers but no help to my problem i havnt strayed more then2-3 clicks then what my racetech sheet says.

Just replace the bushings if you're having the work done.

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I'm a tiny bit confused. First you say the front feels loose, but then you say the forks feel harsh as in, they feel sticky.

Steering head torque is very important on these machines and I've found KTM sets it pretty slack on the bikes from the factory. I always have to give the steering head nut a little tweak before riding because they're just too loose and that causes all sorts of strange feeling from the front end.

These forks do feel harsh initially, they have gobs of stiction. If you take one of the forks off and push on it slowly, it will not feel smooth. Push it hard, break through the stiction barrier and it will go right into the stroke no problem. If it doesn't, then you have another issue. The stiction issues are caused by many things, lack of coatings, bushing type and even too much grease when assembling the seals. I've personally tried everything to make the stiction go away, including machining the lower tubes and polishing the living crap out of them and the inside of the upper tubes, with no success.

Ohh and at 50hrs, the forks don't really need anything but an oil change. I find the bushings and SKF seals last a long time, considerably longer then people think. Besides, once the seals go bad, they loosen up, not get tighter... But you could have something trapped in one of the seals, gob of dirt or something, never know.

Edited by tye1138

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I dont know whats wrong with your tubes tye but the newer WP tubes have very low friction/stiction.

I do agree that they have some stiction right out of the factory. The WP seal grease sucks but I didnt found sealgrease under the seals of a 2013 EXC with 1.5 hours on it last week.

The chrometubes get a little bit of polishing with 2000 grit paper (EU spec), slickoleum grease and modified bushings. Very low friction.

Nobody will deny that the WP piston rod has the lowest friction of all CC forks out there.

Bushings dont last longer than 40 hours. The first pair is wasted after a few hours of riding.

I replaced a set of bushings on a PSF fork with 10 hours on it. You will most certainly confirm that the PSF doenst have as much wear as a coil spring fork. But the bushings were wasted anyway....

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I dont know whats wrong with your tubes tye but the newer WP tubes have very low friction/stiction.

Well, I have 4 sets of WP forks, they all act identical when it comes to stiction.

You can do the same tests I've done:

Pull the cartridge out of the fork tube. Put the fork bottoms (axel clamp) into a vice so the fork is sticking straight up in the air. Then raise the upper tube to the top of the stroke before bottom tube taper and let go. The fork tube will sit there and not move at all. If it does move, it does so extremely slowly.

Now, do the same thing with a modern Showa or KYB fork, the tube will literally drop and go "thud" when it hits the axel clamp.

I have all of these tests on my youtube series, you can check it out below. Mind you, this video is of forks which came right off my new 2013 250SXF with about 10hrs on them, no grease under the seals. Even with Race Tech's lathe work and polishing, they are identical to what's seen in this video:

Nobody will deny that the WP piston rod has the lowest friction of all CC forks out there.

The 2011+ don't have any stiction in the push rod seal. However, oil blows past that seal when the fork fully compresses, which makes the fork harsher until it goes through a full cycle again to de-pressiruze.

Bushings dont last longer than 40 hours.

Never had a problem, the tolerances on all my forks with bushings older then 40hrs, are perfect.

Edited by tye1138

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Well turns out I was alittle wrong I felt my mates ktm fork and they to have alittle Stiction

At top.. BUT the problem with my forks is to stiff of spring or to much preload so I'm guessing there was a mix up with the spring some were along the line.. My symptoms were cornering it wanted to oversteer but when I went to turn in will knife/ washout and feel very loose around 180 corners that any throttle the front end will wash

Jumping seemed ok but when the track got ruff it was nearly Un rideable

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I've done a few WPs. More than 4.

Not gonna start a discussion.

But maybe changing bushings earlier than 40 hours and using proper suspension grease would have been a better idea than buying öhlins forks.

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But maybe changing bushings earlier than 40 hours and using proper suspension grease would have been a better idea than buying öhlins forks.

I did mention the forks in the video were brand new and had only 10hrs on them.

Ohh so WP doesn't put proper suspension grease in their seals. Is that the excuse why WP forks have stiction? WOW if only the rest of the world knew that!

Bro, give it up! Just look at the video, the Öhlins are smooth as silk, the WP forks DON'T MOVE AT ALL!!!!

Sure, you can polish the living crap out of the inside of the uppers and outside of the lowers, you can even re-do the cross-hatching on the tubes and lathe them until they're perfect. However, nothing and I mean nothing beats a fork which works properly out of the box. KYB, Showa, Marzocchi and Öhlins have this nailed. Why is WP so consistently problematic, you'll have to ask them.

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I agree that's why I thought it was Stiction at first because I felt my mates rmz (not air forks) and they were sooo smooth

Even on a mxa right up they went with Showa Akit forks

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Well turns out I was alittle wrong I felt my mates ktm fork and they to have alittle Stiction

Any stiction is a lot, because when you hit something, it takes time to break through the stiction. In that time, all that energy is absorbed by the bike and in a lot of cases, the rider. Stiction is one of MANY issues with the WP forks.

Jumping seemed ok but when the track got ruff it was nearly Un rideable

There are two paths to helping with the ruff stuff. Learn how to ride around the issues with what you have, modifying oil height, adding PHDS rubber bar mounts, maybe messing with the preload or sending the stuff out. OR!!! Buy a different set of forks and forget the problems you had before ever existed for the rest of your life, as the nice thing about investing in different suspension is; you can keep it for life and move it from bike to bike over the years. One of my friends uses his 04' CRF forks on his KTM because... well, they just flat-out work. Rode his bike last weekend, wow... I was impressed!

Edited by tye1138

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Exactly the amount I've spend on them so far would of been better to get ohlins but in saying that I ride my mates 09 250sxf sometimes and man I can blitz through everything fast on that thing even a few a graders have said man your flying.. Then jump back on mine and back to square one haha

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I love my wp forks. They have a slightly longer break in and feel stiff new but it should go away. As far as a lose felling in the front end are your bearings good? Forks aligned? Proper torque on all the bolts? Are they to stiff or are you to far back in the corners? Clickers properly adjusted? Fresh oil? Don't just blow money without doing proper setup to begin with.

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Yep all is perfect I'm 99% sure it's ether spring or to much preload

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