Join Date: Nov 2009
Location: Lander, Wyoming
At engine speeds of 800rpm & above, the KACR pin is retracted and does NOT touch anything.
If you don't see any rotational marks in the front, back or top of the valve cover and the forward lip of the gasket surface of the head, then the KACR flyweights are Not contacting anything and therefore not responsible for the noise that you are hearing.
May I suggest that your valve tappet clearance is possibly too loose? I've never found a metric feeler set in .025mm, only .050mm increments. So I suggest that one should use feelers marked in one thousands increments only for best accuracy.
Tappet clearances should NOT exceed .010inches on exhausts & .008inches on intakes. This is with SNUG fitment of thickest feeler, because we also need to lift the camshaft with the feeler to take up the bearing slack, especially on the RH end of the cams. Cam bearing clearance can be Plasti-Gauged to confirm not worn beyond normal, specs are .00079 - .0024 inches / .020 - .062 mm. Maximum camshaft bearing clearance is a very sloppy .0059inches / .15mm.
Or simply try one size thicker shim on both the RH intake & RH exhaust valves than what you currently have in the engine.
Modify at "YOUR OWN RISK"!
Still riding my 1987 KL650-A1. 83,000+ miles & counting
Last edited by pdwestman; 06-11-2019 at 10:46 AM.