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Well I am new to the supermoto's scene I bought a 04 crf 450r a couple of months ago and decided to check the valve clearance and came up with this,

intake clearance .102 mm - .16 spec clearance + .65 current shim = .592 shim needed
exhaust clearance .356 mm - .28 spec clearance + .88 current shim = .956 shim needed

looked at buying shims but the smallest I could find for crf's are 1.20 mm, double checked the current shim just to make sure i wasn't missing a mm but came up with the same measurement, I doing something wrong here?
if anyone could help it would be much appreciated thank you.
 

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Well I am new to the supermoto's scene I bought a 04 crf 450r a couple of months ago and decided to check the valve clearance and came up with this,

intake clearance .102 mm - .16 spec clearance + .65 current shim = .592 shim needed
exhaust clearance .356 mm - .28 spec clearance + .88 current shim = .956 shim needed

looked at buying shims but the smallest I could find for crf's are 1.20 mm, double checked the current shim just to make sure i wasn't missing a mm but came up with the same measurement, I doing something wrong here?
if anyone could help it would be much appreciated thank you.
1.20mm is the smallest shim you can buy, because at that point the valves are worn in to the head too far, and need replacing. Are your measurements supposed to be "1.592 shim needed" and "1.956 shim needed"? If your clearance is .10 and needs to be .16, just use simple maths to subtract .06 from the current shim size to give that much more clearance. Not easy to explain, it makes sense in my head.

If your current shim is a 1.65 it'll need a 1.59 shim to get correct clearance, you're better off with slightly more clearance, so go next size down which is 1.57 (sometimes listed as 1.575), and the exhaust shim is 1.88 it needs a 1.95 shim to make the correct clearance.
 

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Just want to chime in that if/when you come down to a head refresher, I highly recommend AS Racing in California. They did my 450X head with steel TRX intakes valves. Price/Work/Turnaround were all excellent.

http://www.asracinginc.com/
 

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IF you should need to replace your valves...I recommend Kibblewhite valves.
I was going through valves way too regular in my CRF450 until I went to the Kibblewhites.
After that, valve train maintenance intervals went way down.
 
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