Yamaha WR450F Owner's Service Manual page 54

Cylinder head
Combustion chamber volume
Warpage limit
Camshaft
Drive system
Camshaft cap inside diameter
Camshaft journal diameter
Camshaft-journal-to-camshaft-cap clearance
Camshaft lobe dimensions
Lobe height (Intake)
Limit
Base circle diameter (intake)
Limit
Lobe height (Exhaust)
Limit
Base circle diameter (Exhaust)
Limit
Camshaft runout limit
Timing chain
Tensioning system
Valve, valve seat, valve guide
Valve clearance (cold)
Intake
Exhaust
Valve dimensions
Valve head diameter (intake)
Valve head diameter (exhaust)
Valve face width (intake)
Valve face width (exhaust)
Valve seat contact width (intake)
Valve seat contact width (exhaust)
Valve margin thickness (intake)
Valve margin thickness (exhaust)
Valve stem diameter (intake)
Limit
Valve stem diameter (exhaust)
Limit
Valve guide inside diameter (intake)
Limit
Valve guide inside diameter (exhaust)
Limit
Valve-stem-to-valve-guide clearance (intake)
Limit
Valve-stem-to-valve-guide clearance (exhaust)
Limit
Valve stem runout
ENGINE SPECIFICATIONS
25.98–26.78 cm
0.05 mm (0.0020 in)
Chain drive (left)
22.000–22.021 mm (0.8661–0.8670 in)
21.959–21.972 mm (0.8645–0.8650 in)
0.028–0.062 mm (0.0011–0.0024 in)
37.630–37.730 mm (1.4815–1.4854 in)
37.530 mm (1.4776 in)
27.950–28.050 mm (1.1004–1.1043 in)
27.850 mm (1.0965 in)
33.870–33.970 mm (1.3335–1.3374 in)
33.770 mm (1.3295 in)
24.711–24.811 mm (0.9729–0.9768 in)
24.611 mm (0.9689 in)
0.030 mm (0.0012 in)
Automatic
0.13–0.20 mm (0.0051–0.0079 in)
0.18–0.25 mm (0.0071–0.0098 in)
36.90–37.10 mm (1.4528–1.4606 in)
30.40–30.60 mm (1.1968–1.2047 in)
1.697 mm (0.0668 in)
1.768 mm (0.0696 in)
0.90–1.10 mm (0.0354–0.0433 in)
0.90–1.10 mm (0.0354–0.0433 in)
1.20 mm (0.0472 in)
0.85 mm (0.0335 in)
5.475–5.490 mm (0.2156–0.2161 in)
5.445 mm (0.2144 in)
5.465–5.480 mm (0.2152–0.2157 in)
5.435 mm (0.2140 in)
5.500–5.512 mm (0.2165–0.2170 in)
5.550 mm (0.2185 in)
5.500–5.512 mm (0.2165–0.2170 in)
5.550 mm (0.2185 in)
0.010–0.037 mm (0.0004–0.0015 in)
0.080 mm (0.0032 in)
0.020–0.047 mm (0.0008–0.0019 in)
0.100 mm (0.0039 in)
0.010 mm (0.0004 in)
2-3
3
(1.59–1.63 cu.in)