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Should I Shim?

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Hey guys, I'm new to the forum, been looking around and decided to sign up because I had a question(and am sure I'll have more). I bought a used '04 R off of a local vet rider here a couple weeks ago. It had very low hours on it, I think ~15 or so. Anyways, I have put about another 5 hours on it since, and checked my clearances a few days ago. Both of my exhausts are tight .011, but my intakes had tightened up a bit. My right intake is a loose .004, and my left is a real tight .004. Is it imperitive that I shim them right away, or are they ok because they are still technically in spec? I ask because I will be headed out of state for a trail ride with a bunch of my dads friends next week, and wanted to be sure nothing could get out of control in maybe 10-15 hours of ride time.

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I would reshim that tight .004 before doing 15 more hours. JMO. :)

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You should reshim. some will want to shoot me for saying this but if your in a pinch and do not have the correct shims you can take a knife sharpening wetstone and remove a very small amount of material from your existing shims to get the clearances correct.When your are removing the material.Take a couple cuts on the stone one way then turn the shim 90 degrees and take a couple swipes that way around and so on. That will help insure a square surface.It would be best to use properly ground shims however. :)

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I have both my intakes running at .004 for about 40 hours and have had no problems.... doesnt mean you wont though. .004 is still in spec. If you dont shim them now just bring the tools to do it with you just in case.

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If it was my bike, I would reshim because of the tight .004". 15 hours is decent amount of time before checking the valves again, and the extra thousandth of an inch might help out if the valve moves again. Chances are you will be fine if you don't reshim, but since you are going to have to do it anyways, might as well do it before the ride. Even though the loose .004" is in spec, you might as well shim that one too since you are there.

I'd leave the exhaust valves alone.

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There are many, many, opinions on this subject as it is a well documented subject/issue on Thumpertalk. My advice, as it has been to many folks, is to call Randy at www.fastmannracing.com. Randy has taken care of my bikes and is extremely knowledgeable on the CRF's. The CRF's and their Valve issues are a specialty of his as you will see when you go to his website. GOOD LUCK!!

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