With Vee Two performance Cams, we endeavour to run 0 clearance through the opening and closing cycle to prolong closing shim collet and valve groove life. However it is important that binding does not occur. Due to errors and differences in rocker radii pin positions, etc, a slightly wider tappet clearance than specified may be necessary. Vee Two recommends that piston to valve clearance always be checked.
When checking timing in Desmo engines, not using closing springs, ensure that the bottom rocker is held up against closing shim at position of taking cam timing figures.
Opening and Closing Figures at 0.5mm Lift
Inlet Opening 48 degrees B.T.D.C
Inlet Closing 82 degrees A.B.D.C
Exhaust Opening 80 degrees B.B.D.C
Exhaust Closing 46 degrees A.T.D.C
Maximum Lift at Valve