people 125 Workshop-manual : Page 75

          7. CYLINDER HEAD/VALVES                                                      PEOPLE 125/150

 TORQUE VALUES

 Cylinder head nut                2.0kg-m                       Apply engine oil to threads
 Valve clearance adjusting nut    0.8kg-m                       Apply engine oil to threads


 TROUBLESHOOTING
 · The poor cylinder head operation can be diagnosed by a compression test or by tracing engine
  top-end noises.


 Poor performance at idle speed                      White smoke from exhaust muffler
 · Compression too low                               · Worn valve stem or valve guide
                                                     · Damaged valve stem seal
 Compression too low
 · Incorrect valve clearance adjustment              Abnormal noise
 · Burned or bend valves                             · Incorrect valve clearance adjustment
 · Incorrect valve timing                            · Sticking valve or broken valve spring
 · Broken valve spring                               · Damaged or worn camshaft
 · Poor valve and valve seat contact                 · Worn cam chain guide
 · Leaking cylinder head gasket                      · Worn camshaft and rocker arm
 · Warped or cracked cylinder head contact surface
 · Poorly installed spark plug


 Compression too high
 · Excessive carbon build-up in combustion
  chamber




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