11.CRANKSCASE/CRANKSHAFT/ BALANCE SHAFT ATV 300/250 Remove balance shaft from the left Balance Shaft crankcase. Clean off all gasket material from the crankcase mating surfaces. Avoid damaging the crankcase mating surfaces. Inspect the balance shaft gear teeth. Burrs/chips/roughness/wear Replace. CRANKSHAFT INSPECTION Inspect the crankshaft gear teeth. Burrs/chips/roughness/wear Replace. Measure the connecting rod small end I.D. Service Limit: 17.06 mm (0.6824) 11-4