10-3
dummyheaddummyhead
CYLINDER HEAD/VALVES
SERVICE INFORMATION
GENERAL
• This section covers service of the cylinder head, valves, camshaft and rocker arm.
• The rocker arm services can be done with the engine installed in the frame. The cylinder head, valves and camshaft service
requires engine removal.
• When disassembling, mark and store the disassembled parts to ensure that they are reinstalled in their original locations.
• Clean all disassembled parts with cleaning solvent and dry them by blowing them off with compressed air before inspection.
• Camshaft lubricating oil is fed through oil passages in the cylinder head. Clean the oil passages before assembling cylinder
head.
• Be careful not to damage the mating surfaces when removing the cylinder head cover and cylinder head.
SPECIFICATIONS
Unit: mm (in)
TORQUE VALUES
ITEM STANDARD SERVICE LIMIT
Cylinder compression at 470 min
-1
(rpm) 1,775 kPa (18.1 kgf/cm
2
, 257 psi) –
Valve clearance IN 0.17 ± 0.02 (0.007 ± 0.001) –
EX 0.28 ± 0.02 (0.011 ± 0.001) –
Rocker arm,
rocker arm
shaft
Rocker arm I.D. 20.012 – 20.030 (0.7879 – 0.7886) 20.041 (0.7890)
Rocker arm shaft O.D. 19.972 – 19.993 (0.7863 – 0.7871) 19.961 (0.7859)
Rocker arm-to-shaft clearance 0.019 – 0.058 (0.0007 – 0.0023) 0.08 (0.003)
Cam chain tensioner wedge B length – 6.0 (0.24)
Camshaft Cam lobe height
IN 34.7897 – 35.0297 (1.36967 – 1.37912)
34.7697
(1.36888)
EX 34.9227 – 35.1627 (1.37491 – 1.38436)
34.9027
(1.37412)
Runout – 0.04 (0.002)
Camshaft journal O.D. 41.935 – 41.950 (1.6510 – 1.6516) 41.927 (1.6507)
Valve, valve
guide
Valve stem O.D. IN 4.975 – 4.990 (0.1959 – 0.1965) 4.965 (0.1955)
EX 4.965 – 4.980 (0.1955 – 0.1961) 4.955 (0.1951)
Valve guide I.D. IN/EX 5.000 – 5.012 (0.1969 – 0.1973) 5.04 (0.198)
Stem-to-guide
clearance
IN 0.010 – 0.037 (0.0004 – 0.0015) 0.075 (0.0030)
EX 0.020 – 0.047 (0.0008 – 0.0019) 0.085 (0.0033)
Valve guide
projection above
cylinder head
IN 17.7 – 18.0 (0.70 – 0.71) –
EX 19.6 – 19.9 (0.77 – 0.78) –
Valve seat width IN 0.90 – 1.10 (0.035 – 0.043) 1.5 (0.06)
EX 1.30 – 1.50 (0.051 – 0.059) 1.9 (0.07)
Valve spring free length 49.07 (1.932) 48.1 (1.89)
Cylinder head warpage – 0.10 (0.004)
Cylinder head camshaft journal I.D. 41.995 – 42.019 (1.6533 – 1.6543) 42.027 (1.6546)
Cylinder head-to-camshaft clearance 0.045 – 0.084 (0.0018 – 0.0033) 0.10 (0.004)
ITEM Q'TY
THREAD TORQUE
REMARKS
DIA. (mm) N·m (kgf·m, lbf·ft)
Cylinder head cover socket bolt 3 6 10 (1.0, 7)
Breather plate mounting bolt 8 6 12 (1.2, 9) Apply locking agent to the threads.
Coating width; 6.5 ± 1.0 mm (0.26 ±
0.04 in) except 2.0 ± 1.0 mm (0.08 ±
0.04 in) from tip
Rocker arm shaft bolt 3 8 29 (3.0, 21) Apply engine oil to the threads and
seating surface.
Camshaft maintenance cap 1 36 4.0 (0.4, 3.0) See page 10-11
See page 10-28
Cam chain tensioner bolt 2 6 12 (1.2, 9)
Cam sprocket bolt 1 10 56 (5.7, 41) Apply engine oil to the threads and
seating surface.
Water hose band screw 6 – – See page 10-16
Insulator band screw 1 5 – See page 10-25
Cylinder head special bolt 6 9 44 (4.5, 32) Apply molybdenum oil solution to the
threads and seating surface.
To Next Page
Loading...
Need help?
General
