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Changed springs and now fork issue

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 I changed fork springs with my buddy who bought my old '02. Went through typical process on both bikes, the '02 forks are smooth as butter, my '05 now seems to have a bit of stick wherever you stop compressing forks. They work fine, but have click like sound at the moment of rebound. Both forks do it. We used the same oil and level on both bikes (Spectro 5w @ 350ml), and didn't mess with the cartridge other than removing them. It was smooth before the fork swap, and I don't suspect the springs as they didn't present problems in the previous bike. Both fork sets have pro rebuilds recently FWIW.

 Obviously I need to take them back apart, I just thought I might get some ideas of what to look for. Really feels like something is binding somehow.

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Are you sure that the problem is not related to misalignment of the forks? Or do you mean they are stiff even when not installed on the bike?

Edited by unboundnrg

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As stated above make sure everything is aligned properly. How tight did you make the triple clamp bolts? Over tight will cause binding. Improper installation of the axle will cause binding.

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Not related to triple clamps, I noticed this before I put forks into clamps. I know not to over tighten clamps. The springs are 48kg

 

Thanks for the feedback guys

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Not all springs are the exact same length.  There are slight variations in preload.  It's possible you have zero preload at full extension, and are hearing the springs rattle.  Did you thread the bottom center bolt and stopper "nut" on fully?

 

Are you bottoming out the forks?

 

Do you know the correct technique for aligning the front axle with the two forks?

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Not all springs are the exact same length.  There are slight variations in preload.  It's possible you have zero preload at full extension, and are hearing the springs rattle.  Did you thread the bottom center bolt and stopper "nut" on fully?

 

Are you bottoming out the forks?

 

Do you know the correct technique for aligning the front axle with the two forks?

 I can't say how much preload the spring has, but it seemed the threads on the cartridge bottom weren't exposed without compressing forks, so that would lead me to believe there is some preload. I'm quite sure the rebound nut is threaded into to stopper firmly. The noise I'm am hearing happens at any compression point, far prior to fork bottoming.

 Yes, I am aware of fork alignment procedure, but given that the forks make said noise out of the bike, it leads me to believe it's a bind of some sort, and not fork alignment. I rode the bike today, but I will take forks apart and take a closer look before next ride.

 

Thanks for weighing in on this

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Also check the tension on the steering stem bearings, and handlebar clamp bolts.  And condition of the front wheel bearings.  Sometimes mechanical noises can resonate through other parts.

 

Did you split the fork upper and lower tubes when you swapped springs?  Have you checked the tightness of the cartridge's upper threads into the fork tube, and the base valve threads into the cartridge?

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New bushings wouldn't hurt. Just go for oem since non oem bushings are known from binding and stiction.

Edited by unboundnrg

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Also check the tension on the steering stem bearings, and handlebar clamp bolts.  And condition of the front wheel bearings.  Sometimes mechanical noises can resonate through other parts.

 

Did you split the fork upper and lower tubes when you swapped springs?  Have you checked the tightness of the cartridge's upper threads into the fork tube, and the base valve threads into the cartridge?

The forks make the noise (you can feel it as well) in or out of the bike. I'm 100% confident the trouble is in the fork and not clamp, wheel, etc. No, I did not separate the fork tubes. The cartridges came out, springs swapped and back together. There must be a bind between cartridge and spring somewhere. These springs didn't bind in the '02 forks they came from. Yup, upper and lower cartridge threads are tight.

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New bushings wouldn't hurt. Just go for oem since non oem bushings are known from binding and stiction.

Can't hurt, but forks were pro rebuilt / woods revalve less than 12 hours ago

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Check to make sure the two springs are the same diameter.

In 03 honda made the compression vavle piston biggeron the cr 250. This would.increase the tube size up at the comp stack. Maybe the rest of the caritrage tube increased to. This would be why you spring is clicking as you cycle the forks.

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I've swapped springs between '02 and later forks, so they are compatible.

 

Did the springs slide easily into and out of the fork tubes?  Did they get pinched in place toward the lug end of the tubes?  If so, someone used too long fork guard bolts and dented the lower tube inward slightly.

 

Are the forks functioning correctly, in terms of damping?

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Check to make sure the two springs are the same diameter.

In 03 honda made the compression vavle piston biggeron the cr 250. This would.increase the tube size up at the comp stack. Maybe the rest of the caritrage tube increased to. This would be why you spring is clicking as you cycle the forks.

It could be that, I measured both ends to make sure there wasn't a big/small end like on the shocks. But I didn't measure the springs. I have always seen fork springs listed for 00-07 CR250, certainly 02-07, but something is making contact that shouldn't be.

Take the entire fork apart and put it back together PER MX MAINT MANUAL?

Yup, that's the plan, always good to fish for ideas before hand though.

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I've swapped springs between '02 and later forks, so they are compatible.

 

Did the springs slide easily into and out of the fork tubes?  Did they get pinched in place toward the lug end of the tubes?  If so, someone used too long fork guard bolts and dented the lower tube inward slightly.

 

Are the forks functioning correctly, in terms of damping?

Springs move freely in the tubes, that's what makes me suspect cartridge/spring interference. But doesn't sound like a common issue. Oh, and the fork tubes moved freely without spring/cartridge too. The forks function well, but I imagine that little bit of bind at end stroke isn't helping anything.

I have always had my suspension work handled by pro's. My goal is to get set-up to at least be able to handle rebuilding them.

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I just did a complete rebuild on my forks strictly following the service manual. It wasnt that difficult for my 1st time. Check your spring length and run-out where it sais to, and for worn parts like the bushings where it sais. You really need a manual to do it right. I mean, since your having problems w ur forks....

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