My '03 CRF450R has become extremely hard to start. Once started all is fine, including restart. I was told the valves needed adjusting so I took the cover off to check my tolerances. My exhaust valves are within tolerance, my rocker arm needed slight adjustment, however I was unable to get even a 0.001" feeler gauge between the CAM and intake valve. I would have thought the valve clearance would have increase with wear, rather than decrease.
Assuming this decreased clearance was measured correctly, Will I need to remove shims rather than add them, or will the entire valve and or spring need to be replaced?
Also, is the special tool shown in the manual necessary or will some other common tool suffice?