3. INSPECTION/ADJUSTMENT MXU 250R/300R Gap, Wear, and Fouling Deposits Measure the spark plug gap. Spark Plug Gap: 0.60.7 mm (0.002 0.003 in) When installing, first screw in the spark plug by hand and then tighten it with a spark plug wrench. Washer Deformation Cracks, Damage Cylinder Head Cover VALVE CLEARANCE Inspect and adjust valve clearance while the engine is cold (below 35). Remove the cylinder head cover. (See chapter 7) Index Mark "T" Mark Turn the flywheel clockwise so that the "T" mark on the flywheel aligns with the index mark on the right crankcase cover to bring the round hole on the camshaft gear facing up to the top dead center on the compression stroke. Inspect and adjust the valve clearance. Valve Clearance: IN: 0.1 mm (0.004 in) EX: 0.1 mm (0.004 in) 3-8