6. CYLINDER HEAD/VALVES GRAND DINK 125/150 SERVICE INFORMATION GENERAL INSTRUCTIONS · The cylinder head can be serviced with the engine installed in the frame. Coolant in the radiator and water jacket must be drained first. · When assembling, apply molybdenum disulfide grease or engine oil to the valve guide movable parts and valve arm sliding surfaces for initial lubrication. · The valve rocker arms are lubricated by engine oil through the cylinder head engine oil passages. Clean and unclog the oil passages before assembling the cylinder head. · After disassembly, clean the removed parts and dry them with compressed air before inspection. · After removal, mark and arrange the removed parts in order. When assembling, install them in the reverse order of removal. SPECIFICATIONS Standard (mm) Service Limit (mm) Item SH30DA SH25DA SH30DA SH25DA Valve clearance (cold) IN 0.10 0.10 EX 0.10 0.10 Cylinder head compression pressure 15kg/cm 15kg/cm Cylinder head warpage 0.05 0.05 Camshaft cam height IN 30.8763 30.8763 30.75 30.75 EX 30.4081 30.4081 30.26 30.26 Valve rocker arm I.D. IN 10.0010.018 10.0010.018 10.10 10.10 EX 10.0010.018 10.0010.018 10.10 10.10 Valve rocker arm shaft IN 9.9729.987 9.9729.987 9.9 9.9 O.D. EX 9.9729.987 9.9729.987 9.9 9.9 Valve seat width IN 1.2 1.2 1.8 1.8 EX 1.2 1.2 1.8 1.8 Valve stem O.D. IN 4.9904.975 4.9904.975 4.925 4.925 EX 4.9704.955 4.9704.955 4.915 4.915 Valve guide I.D. IN 5.005.012 5.005.012 5.03 5.03 EX 5.005.012 5.005.012 5.03 5.03 Valve stem-to-guide IN 0.0100.037 0.0100.037 0.08 0.08 clearance EX 0.0300.057 0.0300.057 0.10 0.10 TORQUE VALUES Cylinder head cap nut 19.6N-m Apply engine oil to threads Valve clearance adjusting nut 8.8N-m Apply engine oil to threads Cylinder head cover bolt 7.811.8N-m SPECIAL TOOLS Valve spring compressor Valve seat cutter, 24.5mm 45° IN-EX Valve seat cutter, 25mm Plane cutter 37.5° EX Valve seat cutter, 22mm Plane cutter 37.5° EX Valve seat cutter, 26mm Plane cutter 63.5° IN/EX Cutter clip Valve guide driver Valve guide reamer 6-2