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pCp 252
12/8/2016 9:19pm
12/8/2016 9:19pm
Has anyone took a 3.00mm valve shim and shaved away 1/100th's of a MM or whatever to create say a 2.975 shim? If so, whats the best way using common tools to evenly shave away some material on the shim? I have a digital caliper to check.
Reason I want to do this is because a 2.95 shim leaves too much clearance, and a 3.00 leaves too little clearance.
On a similar note, which way do the experts err on regarding valve clearance? For example, the KX250F exhaust valve clearance spec is between .17 and .22mm. Should I aim for .17 or .22? Or does it not make a difference?
Reason I want to do this is because a 2.95 shim leaves too much clearance, and a 3.00 leaves too little clearance.
On a similar note, which way do the experts err on regarding valve clearance? For example, the KX250F exhaust valve clearance spec is between .17 and .22mm. Should I aim for .17 or .22? Or does it not make a difference?
For clearance, you have .05 range. Go for the middle. .19-.20
Paw Paw
A team green mechanic shimmed my bike at Broome Tioga one year. He said if you have a range of say 0.004" to 0.006" that you should be able to fit a 0.004" feeler gauge, but not a 0.006". I've done this for 12 years now with great success
The Shop
In regards to what clearance, aiming for the low side will slightly ease the impact of lobes on buckets and barely effect lift/duration. I was told when I purchased cams from Pro Circuit to set clearances at .004", not .004-.006, just .004. That was on intake and exhaust on both kx250f and crf250.
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