8. CYLINDER HEAD/VALVES MXU 500 IRS Install the cam chain over the cam sprockets Punch Marks and then install the intake and exhaust camshafts. Install each camshafts to the correct locations. "IN": no decompressor cam "EX": has a decompressor cam Make sure the timing marks on the cam sprockets are flush with the cylinder head upper surface and punch marks Timing Marks face upward as shown. Install intake and exhaust camshaft holders to the correct locations. Install each camshaft holders to the correct locations. "IN": no stop pin. "EX": has a stop pin. Exhaust Camshaft Holder Stop Pin 8-12