6. CYLINDER HEAD/VALVES DOWNTOWN 125i ASSEMBLY Rocker Arm Shafts Apply engine oil to the rocker arms and rocker arm shafts. Install the rocker arms and shafts into the camshaft holder. · Install the exhaust valve rocker arm shaft on the "EX" side of the camshaft holder · Clean the intake valve rocker arm shaft off any grease before installation. 6-7