Yamaha WR250F 2016 Owner's Service Manual page 56

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
12.07–12.87 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)
31.730–31.830 mm (1.2492–1.2531 in)
31.630 mm (1.2453 in)
22.450–22.550 mm (0.8839–0.8878 in)
22.350 mm (0.8799 in)
33.370–33.470 mm (1.3138–1.3177 in)
33.270 mm (1.3098 in)
25.211–25.311 mm (0.9926–0.9965 in)
25.111 mm (0.9886 in)
0.030 mm (0.0012 in)
Automatic
0.12–0.19 mm (0.0047–0.0075 in)
0.17–0.24 mm (0.0067–0.0094 in)
30.90–31.10 mm (1.2165–1.2244 in)
24.90–25.10 mm (0.9803–0.9882 in)
1.697 mm (0.0668 in)
1.909 mm (0.0752 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)
4.975–4.990 mm (0.1959–0.1965 in)
4.945 mm (0.1947 in)
4.460–4.475 mm (0.1756–0.1762 in)
4.430 mm (0.1744 in)
5.000–5.012 mm (0.1969–0.1973 in)
5.050 mm (0.1988 in)
4.500–4.512 mm (0.1772–0.1776 in)
4.550 mm (0.1791 in)
0.010–0.037 mm (0.0004–0.0015 in)
0.080 mm (0.0032 in)
0.025–0.052 mm (0.0010–0.0020 in)
0.100 mm (0.0039 in)
0.010 mm (0.0004 in)
2-3
3
(0.74–0.79 cu.in)