6. CYLINDER HEAD/VALVES DINK 50/ 125
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(DINK 125) Unit: mm (in)
Item Standard Service Limit
Valve clearance (cold) IN 0.1 (0.004)
EX 0.1 (0.004)
Cylinder head compression pressure 15 kg/cm(1500 kpa, 213 psi)
Cylinder head warpage 0.05 (0.002)
Camshaft cam height IN 30.8763 (1.235052) 30.75 (1.23)
EX 30.4081 (1.216324) 30.26 (1.2104)
Valve rocker arm I.D. IN 1010.018 (0.40.40072) 10.1 (0.404)
EX 1010.018 (0.40.40072) 10.1 (0.404)
Valve rocker arm shaft IN 9.9729.987 (0.398880.39948) 9.9 (0.396)
O.D. EX 9.9729.987 (0.398880.39948) 9.9 (0.396)
Valve stem O.D. IN 4.994.975 (0.19960.199) 4.925 0.197)
EX 4.974.955 (0.19880.1982) 4.915 (0.1966)
Valve guide I.D. IN 55.012 (0.20.20048) 5.03 (0.2012)
EX 55.012 (0.20.20048) 5.03 (0.2012)
Valve stem-to-guide IN 0.010.037 (0.00040.00148) 0.08 (0.0032)
clearance EX 0.030.057 (0.00120.00228) 0.1 (0.004)
clearance EX
6-3
