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Forks ability to soak up small hits has become worse why???

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My '01 wr426 forks have Gold Valves, and shim stacks to suit my riding style (off-road with rocks, little MX). After working with a tuner we got it perfect. They would soak up small bumps/rocks very well, yet still were good on big hits. Then, after a crash where the front wheel got tweaked to the left a little, they had become harsh again. I re-tweaked them back into position on the same ride and they got -pretty- good again. I did ride a little while with them tweaked (10min or so). Before and after this ride the right fork had a slight leak.

After the ride I had the tuner eval the whole right fork leg. He put in new bushings and fork seal, and cleaned the valve and shim stack and matched the oil heights (90mm I think). Off the bike, the fork action is smooth and not sticky so I don't think the tube is bent. The left leg only needed an oil change.

After all that work the fork is still way too stiff on small hits. I bled the air, and tried rebound settings of min/half/max against most settings on the compression clickers. The settings of the clickers seem to make very little difference!

So, what could be wrong with a fork that would cause this problem? We haven't looked at the left leg yet, but that is next if I don't get some other ideas.

Thanks

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Make sure your forks are exactly the same ht. as each other and that the R/S fork is not bound up on the axle.

doc

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Doc,

The forks are the same height, well within 1mm of each other. As far as the axle binding problem, I did the procedure described in the manual, apply grease to the axle, tighten the large nut on the L/S push the handlebars and compress the forks a bunch. Tighten the left side axle nuts, compress them some more then tighten the right side. And of course everything is properly torqued, including the triple clamp nuts.

How do you tell if it's bound, is there something you can see? Any other ideas?

Thanks

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You need to get a caliper and measure your fork ht. for sure. 1 mm off is not good.

With the bike on a stand loosen the 2 R/S axle pinch bolts. Then take a small straightblade screwdriver and carefully tap it into the slot between the bolts. Now you can take and move the R fork leg back and forth untill you can actually see that there is no binding. It should almost center itself.

doc

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90mm seems like a lot of oil for tral riding. You could be giving up plushness for bottoming resistance. What was the oil ht before the crash?

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Definitely not 90 it ain't no MX bike! ...try 110-125 then you can add for stiffness - and more adj with compression.

A crash will rarely affect fork bind unless the fork is tweaked or bent - the leaky seal will - remove the foks and service with new seals and new oil - new oil height - you will be happier

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How was the 90 mm's oil ht. measured? If he set it at 90mm's and then pulled the outer tube fully up once and reset it at 90 again then you would actually end up with approx 105mm's.

Still, like Ga426owner and killhill said a little lower would be better.

doc

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I will ask him and see how he measured it. During this process, I set it myself once at 125mm and it didn't make much difference. Since the air in the fork functions as a secondary spring, I thought that the oil height made most of the difference in the last 1/3 of the travel. This problem is in the first 1/2 or so.

I'll check the height myself. To set an actual height of 125mm, do I just take the forks off and springs out, lower the outer tube, and set to 125? Or does it need pumping first?

Ga426, the seal bushings and oil are all new.

Thanks!

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