Yamaha MBK MW125 2014, Service Manual

Page: 32 / 380

ENGINE SPECIFICATIONS
2-3
Spark plug(s)
Manufacturer/model NGK/CR7E
Spark plug gap 0.7–0.8 mm (0.028–0.031 in)
Cylinder head
Warpage limit 0.05 mm (0.0020 in)
Camshaft
Drive system Chain drive (left)
Camshaft lobe dimensions
Lobe height (Intake) 30.757–30.857 mm (1.2109–1.2148 in)
Limit 30.657 mm (1.2070 in)
Base circle diameter (Intake) 26.550–26.650 mm (1.0453–1.0492 in)
Lobe height (Exhaust) 30.790–30.890 mm (1.2122–1.2161 in)
Limit 30.690 mm (1.2083 in)
Base circle diameter (Exhaust) 26.631–26.731 mm (1.0485–1.0524 in)
Camshaft runout limit 0.030 mm (0.0012 in)
Rocker arm/rocker arm shaft
Rocker arm inside diameter 9.985–10.000 mm (0.3931–0.3937 in)
Limit 10.015 mm (0.3943 in)
Rocker arm shaft outside diameter 9.966–9.976 mm (0.3924–0.3928 in)
Limit 9.936 mm (0.3912 in)
Rocker-arm-to-rocker-arm-shaft clearance 0.009–0.034 mm (0.0004–0.0013 in)
Limit 0.080 mm (0.0032 in)
Valve, valve seat, valve guide
Valve clearance (cold)
Intake 0.08–0.12 mm (0.0032–0.0047 in)
Exhaust 0.16–0.20 mm (0.0063–0.0079 in)
Valve dimensions
Valve head diameter (intake) 25.90–26.10 mm (1.0197–1.0276 in)
Valve head diameter (exhaust) 21.90–22.10 mm (0.8622–0.8701 in)
Valve seat contact width (intake) 0.90–1.20 mm (0.0354–0.0472 in)
Limit 1.6 mm (0.06 in)
Valve seat contact width (exhaust) 0.90–1.20 mm (0.0354–0.0472 in)
Limit 1.6 mm (0.06 in)
Valve stem diameter (intake) 4.975–4.990 mm (0.1959–0.1965 in)
Limit 4.920 mm (0.1937 in)
Valve stem diameter (exhaust) 4.960–4.975 mm (0.1953–0.1959 in)
Limit 4.925 mm (0.1939 in)
Valve guide inside diameter (intake) 5.000–5.012 mm (0.1969–0.1973 in)
Limit 5.050 mm (0.1988 in)
Valve guide inside diameter (exhaust) 5.000–5.012 mm (0.1969–0.1973 in)
Limit 5.050 mm (0.1988 in)
Valve-stem-to-valve-guide clearance (intake) 0.010–0.037 mm (0.0004–0.0015 in)
Limit 0.080 mm (0.0032 in)
Valve-stem-to-valve-guide clearance (exhaust) 0.025–0.052 mm (0.0010–0.0020 in)
Limit 0.110 mm (0.0043 in)
Valve stem runout 0.010 mm (0.0004 in)