6. CYLINDER HEAD/VALVES                                       DINK 50/ 125


 INSPECTION
                                                  Combustion Chamber
 Remove carbon deposits from the exhaust
 port and combustion chamber.
 Be careful not to damage the cylinder
   head mating surface.




                                                              Exhaust Port



 Valve /Valve guide

 Inspect each valve for bending, burning,
 scratches or abnormal stem wear.
 If any defects are found, replace the valve
 with a new one.

 Check valve movement in the guide.
 Measure each valve stem O.D.
 Measure each valve guide I.D.
 Subtract each valve stem O.D. from the
 corresponding guide I.D. to obtain the
 stem-to-guide clearance.
 Service limits:
                    IN: 0.08 mm (0.0032 in)
                   EX: 0.1 mm (0.004 in)
 If the stem-to-guide clearance exceeds
   the service limits, replace the cylinder
   head is necessary.




 Valve spring

 Measure the free length of the inner and outer
 valve springs.

 Service Limit:
                  Inner: 29.3 mm (1.172 in)
                  Outer: 32 mm (1.28 in)



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