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YZ400f valve help please

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Probably a dumb question (or a few) but bare with me, im new. I installed a yz450f decompression exhaust cam in my 99 yz400f. After getting everything torqued back in, I did a valve clearance check. I checked clearances before and then after (youll see picture attached showing both readings). Changing the exhaust cam actually brought my clearances into spec on the Exhaust side. However, one of my intake clearances (the one closest to cam chain) is out of spec sitting at .08 . However, everytime i am online looking for valve shims, they always state yz450f shims. So my question to everyone is are the shim sizes the same for both the yz400f and yz450f as in are they interchangeable? Also, based off the clearances you see in the pic attached, would you think with the difference in clearance being that much is normal or a sign of some other wear? Thanks again in advance.

IMG_5646.JPG

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Was it a used cam you put in there or a brand new one? I would think that if it was used and had a good deal of wear, there could be a chance there could be more clearance.i am assuming you cycled the engine a few times after you reassembled before you measured.

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Yes the shims are interchangeable - 9.48mm

Just shim that low intake and keep an eye on it - titanium intake valves wear quicker than exhaust (if they are titanium)

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I bought the cam used but it looks like it is in pretty good condition. I however, did not cycle the engine at all so maybe I should do that and then check clearance is again?? As for the intake valves being titanium., i believe they are stainless steel for this model.

 

 

Thanks again fellas

 

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I would suggest measuring again. Especially if she's still apart just to make sure. Best of luck!

I will for sure. Thanks again for the advice everyone.
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