8. CYLINDER HEAD/VALVES                                                                   UXV 500


 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                                                                      Unit: mm (in)
            Item                                    Standard                     Service Limit
                               IN      0.1 mm (0.004 in)                              
 Valve clearance (cold)
                               EX      0.1 mm (0.004 in)                              
 Cylinder head compression pressure    15 kg/cm2 (1500 kPa, 213 psi)                  
 Cylinder head warpage                                                      0.05 (0.002)
 Camshaft runout                                                            0.05 (0.002)
                               IN      37.2614 (1.4905)                     37.11 (1.4844)
 Camshaft cam height
                               EX      37.0084 (1.4803)                     36.86 (1.4744)
                               IN      10 (0.4)10.015 (0.4006)              10.1 (0.404)
 Valve rocker arm I.D.
                               EX      10 (0.4)10.015 (0.4006)              10.1 (0.404)
 Valve rocker arm shaft        IN      9.975 (0.399)9.99 (0.3996)           9.9 (0.396)
 O.D.                          EX      9.975 (0.399)9.99 (0.3996)           9.9 (0.396)
 Rocker arm to shaft clearance         0.009 (0.0004)0.042 (0.0017)         0.1 (0.004)
                               IN      4.975 (0.199)4.99 (0.1996)           4.925 (0.197)
 Valve stem O.D.
                               EX      4.955 (0.1982)4.97 (0.1988)          4.915 (0.1966)
                               IN      5 (0.2)5.015 (0.2006)                5.03 (0.2012)
 Valve guide I.D.
                               EX      5 (0.2)5.015 (0.2006)                5.03 (0.2012)
 Valve stem-to-guide           IN      0.01 (0.004)0.037 (0.0015)           0.08 (0.0032)
 clearance                     EX      0.03 (0.0012)0.057 (0.0023)          0.1 (0.004)




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