kxr maxxer 250 300 Werkstatthandbuch : Seite 90

          7. CYLINDER HEAD/VALVES                                                             ATV 300/250


 SERVICE INFORMATION
 GENERAL INSTRUCTIONS
 · The cylinder head can be serviced with the engine installed in the frame.
 · When assembling, apply molybdenum disulfide grease or engine oil to the valve guide movable
   parts, valve arm and camshaft sliding surfaces for initial lubrication.
 · The camshaft is 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 (0.004)                                     
 Valve clearance (cold)
                               EX  0.1 (0.004)                                     
 Cylinder head compression ATV 250 152 kgf/cm (1500 kPa, 213 psi)                  
 pressure                  ATV 300 162 kgf/cm (1600 kPa, 227 psi)                  
 Cylinder head warpage                                                      0.05 (0.0002)
                               IN  34.287 (1.3715)                          34.15 (1.366)
 Camshaft cam height
                               EX  34.1721 (1.3669)                         34.05 (1.362)
 Valve rocker arm to shaft 0.0340.09 (0.00140.0036)                         0.1 (0.004)
 Valve stem-to-guide           IN  0.010.037 (0.00040.0015)                 0.06 (0.0024)
 Clearance                     EX  0.0250.052 (0.0010.0021)                 0.08 (0.0032)
                               IN  30.9 (1.236)                             29.4 (1.176)
 Valve spring free length
                               EX  41 (1.64)                                39 (1.56)
 Valve spring compressed       IN  10.2011.84 kg (at 18.05 mm)                     
 force                         EX  19.1422.02 kg (at 21.5 mm)                      
                               IN  0.8 (0.032)                                     
 Valve spring tilt
                               EX  1.07 (0.0428)                                   




 TORQUE VALUES
 Cylinder head cover bolt        1 kgf-m ( 10 Nm, 7.2 lbf-ft)
 Cam shaft hold nut              2.5 kgf-m (25 Nm, 18 lbf-ft)    Apply engine oil to threads
 Tappet adjusting nut            0.9 kgf-m (9 Nm, 6.5 lbf-ft)    Apply engine oil to threads


 SPECIAL TOOLS
 Valve spring compressor            E040
 Tappet adjuster                    E012




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