Yamaha YZFR1W 2007, Service Manual

Page: 32 / 429

ENGINE SPECIFICATIONS
2-4
Valve face width B (intake) 1.200–2.480 mm (0.0472–0.0976 in)
Valve face width B (exhaust) 1.625–2.900 mm (0.0640–0.1142 in)
Valve seat width C (intake) 0.90–1.10 mm (0.0354–0.0433 in)
Valve seat width C (exhaust) 0.90–1.10 mm (0.0354–0.0433 in)
Valve margin thickness D (intake) 1.10–1.50 mm (0.0433–0.0591 in)
Valve margin thickness D (exhaust) 0.50–0.90 mm (0.0197–0.0354 in)
Valve stem diameter (intake) 4.975–4.990 mm (0.1959–0.1965 in)
Limit 4.960 mm (0.1953 in)
Valve stem diameter (exhaust) 4.460–4.475 mm (0.1756–0.1762 in)
Limit 4.425 mm (0.1742 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) 4.500–4.512 mm (0.1772–0.1776 in)
Limit 4.550 mm (0.1791 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 0.100 mm (0.0039 in)
Valve stem runout 0.010 mm (0.0004 in)
Cylinder head valve seat width (intake) 0.90–1.10 mm (0.0354–0.0433 in)
Cylinder head valve seat width (exhaust) 0.90–1.10 mm (0.0354–0.0433 in)
Valve spring
Inner spring
Free length (intake)
39.79 mm (1.57 in)
Free length (exhaust)
38.42 mm (1.51 in)
Installed length (intake) 35.50 mm (1.40 in)
Installed length (exhaust) 33.00 mm (1.30 in)
Spring rate K1 (intake) 42.91 N/mm (245.02 lb/in) (4.38 kgf/mm)
Spring rate K2 (intake) 56.23 N/mm (321.07 lb/in) (5.73 kgf/mm)
Spring rate K1 (exhaust) 40.10 N/mm (228.97 lb/in) (4.09 kgf/mm)
Spring rate K2 (exhaust) 51.85 N/mm (296.06 lb/in) (5.29 kgf/mm)