Adjusting the shims in the cylinder head of my Triumph stag, Have measured them with a mic and started checking them with feeler gauges, Here are the tolerances INLET 0,006"-0,008" (0'15-0·20 mm.) EXHAUST 0,016"-0,018" (0'4-0'45 mm.) On some of my inlet valves I am getting readings from the feeler gauge 0.010” is this accept able or do I need to change the Shims, How close to the tolerances do I need to be ?