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tight valves

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I bought a brand new 2006 head with valves and cams from ebay for my 02 last year. Seller said the recall was done. I bought an hourmeter after an estimated 20 hours, and it shows 26 hours by now. So I'm assuming that the bike has an estimated 45-50 hours. We're mostly riding tight motocross track.

I checked the valves today and they are extremely tight. 0.07 for intake and 0.08 for exhaust. Is this normal for 50 hrs? isn't it a bit early? What about Yamaha reliability? :thumbsup:

I'm going to re-shim the valves this week. Should I buy new valve and spring set and change after a few adjustments?

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50 hrs is pretty good

Shimming them is not hard, its a small task for 50 hours of use

Thats yamaha reliability for ya

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I don't think it's hard to re-shim :thumbsup: I just say that is that too tight for 50hrs. The measurements are in millimeters, 0.07mm for intake and 0.08mm for ex. I live in Turkey and getting parts here takes a couple of weeks. What I'm asking is should I buy a new set to be ready for a rebuild. Will it need a rebuild soon?

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I don't think it's hard to re-shim :thumbsup: I just say that is that too tight for 50hrs. The measurements are in millimeters, 0.07mm for intake and 0.08mm for ex. I live in Turkey and getting parts here takes a couple of weeks. What I'm asking is should I buy a new set to be ready for a rebuild. Will it need a rebuild soon?

Was there any time on the valves before you got the head, or where the valves brand new? Either way, 50 hours before the first shim job is average. You will probably have to shim again at about the 75-80 hour mark and then they will probably tighten up again at about the 90-100 hour mark, which I would change the valves at that point if I were you. Keep a clean air filter in it, as the number one cause of fast wearing valves is dirt getting into the engine.

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ive got 60 some hours on my 07 yz250f and i havent checked the valves ever, looked at them the other day and they were: ex : 26 .25 and intake .20 .17... yeah....about that

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