8. CYLINDER/PISTON MXU 300/250 Intake Side Guide Inspect the exhaust side and intake side chain guides. Wear/Damage Replace. Exhaust Side Guide PISTON INSTALLATION "IN" Mark Remove any gasket material from the crankcase surface. Be careful not to drop foreign matters into the crankcase. IN Install the piston, piston pin and a new piston pin clip. · Position the piston "IN" mark on the intake valve side. · Place a clean shop towel in the crankcase to keep the piston pin clip from falling into the crankcase. CYLINDER INSTALLATION Install the dowel pins and a new cylinder gasket on the crankcase. Coat the cylinder bore, piston and piston rings with clean engine oil. Carefully lower the cylinder over the piston by compressing the piston rings. · Apply proper clean engine oil around cylinder wall. · Be careful not to damage or break the piston rings. · Stagger the ring end gaps at 120° to the piston pin. 8-9