New here with valve shim question

Hello all, first post here. Just recently after a break from riding that lasted about 3 years or so, I decided to jump back into it. I have an '04 YZ450F and an '06 YZ250. I decided that before I started riding the 450 again, I needed to check the valve clearances. The two exhaust valves are about .18-19mm. Just out of spec. All three intake valves were in the .10-.15mm range so I'm good there. Now, I have never done any kind of valve work on anything so I'm probably going to sound like a newb. It would seem to me that I would need a smaller (thinner) shim to increase the distance between the lobe and the bucket and get it back up into that .20-.25mm spec. Am I right or wrong?

Also, what shim kit would you guys recommend?

Thank you.

You're right. But I recommend no shim kit unless you are going to be working on three different bikes.

You have two valves out by a single shim size or less. Buy two shims and be done with it. Shim kits are $70-80 or better and give you 3 of each size. That includes about 28 sizes you won't ever use on a YZF, BTW. You can get "refill packs" from Hot Cams in shorter size ranges for half as much with 5 each of shims you may actually use one day, though.

BTW, if your Yamaha dealer doesn't have them in stock check with the Honda shop. The same shims are used in the CRF450. They'll have plenty on hand.

Also, you should have a manual:


Thank you grayracer :thumbsup:

I will definately get the refill kit over the other.

Also, thanks for the links.

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