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Valve shims

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Just checked the valves on a 2004 crf250r I purchased off CL. Valves are in spec, L In-.005 and R In .005 but my question is about shim thickness. The intake shims are 1.69 and 1.71. At what shim thickness, is it time to change the valves? BTW, the exhaust was good as well. L Ex. .012 and R Ex. .011 and shim thickness was 2.38 on both sides.

The only reason I even checked this was just an overall assessment of a "new to me" machine.

Thanks.

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1.25 or 1.3 are the smallest shims. Once the (titanium) intakes start getting tight though it means the external coating is worn off and it will be time for a rebuild soon. Shimming just buys a few extra hours.

The shim sizes you've got in there are likely what were put in after the last valve job (haven't moved yet) so keep up on maintenance and you should be good for a while yet.

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Thanks. That's what I was thinking but, I am new to this so I just wanted a second opinion. I'm just nervous because I have read that the '04 likes to destroy valves.

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Yeah the early crf250's were bad for intake valves. There's a chance the previous owner has upgraded them already though. If they do go on you, two good options are using stainless steel intakes or send it in to Fastheads and get beryllium copper seats put in. I did the Fastheads thing and although it's a lot more expensive than the stainless option - they last forever and allow you to continue to run titanium valves and OEM parts so the performance and remainder of the valve train function as designed. I sold mine with over 130 hours on the Fastheads valve setup and they never budged.

Edited by sjvmtb
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Yeah the early crf250's were bad for intake valves. There's a chance the previous owner has upgraded them already though. If they do go on you, two good options are using stainless steel intakes or send it in to Fastheads and get beryllium copper seats put in. I did the Fastheads thing and although it's a lot more expensive than the stainless option - they last forever and allow you to continue to run titanium valves and OEM parts so the performance and remainder of the valve train function as designed. I sold mine with over 130 hours on the Fastheads valve setup and they never budged.

how much did that fast heads seats cost you ?

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how much did that fast heads seats cost you ?

I have the same setup... paid  around 240 for parts/installation for bronze guides and copper beryllium seats. That was about a year ago and I bought valves from him aswell and was having some bottom end work done as well so ymmv. 1 year warranty on that head setup which is pretty much unheard of on these bikes.

 

Only have 30 hours on them but did have a improperly installed air filter on a dusty ride in the first 5 hours. Haven't moved.

Edited by problem_child

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how much did that fast heads seats cost you ?

I think my whole setup was $800-900. That got a wiseco piston kit plus the full head work - BeCu seats, del west Ti intakes, Kibblewhite SS exhaust valves, springs, guides, etc.

They used to have the prices for their different packages on their website...

Edited by sjvmtb

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I see they have a service in ebay for like 300 bucks or something I can install the valves myself. Would just wanna have them cut and upgrade the head.

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