Yamaha WR125R 2009, Service Manual

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ENGINE SPECIFICATIONS
2-4
Tensioning system Automatic
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 9.941 mm (0.3914 in)
Rocker-arm-to-rocker-arm-shaft clearance 0.009–0.034 mm (0.0004–0.0013 in)
Limit 0.074 mm (0.0029 in)
Valve, valve seat, valve guide
Valve clearance (cold)
Intake 0.10–0.14 mm (0.0039–0.0055 in)
Exhaust 0.20–0.24 mm (0.0079–0.0094 in)
Valve dimensions
Valve head diameter A (intake) 19.40–19.60 mm (0.7638–0.7717 in)
Valve head diameter A (exhaust) 16.90–17.10 mm (0.6654–0.6732 in)
Valve face width B (intake) 1.538–2.138 mm (0.0606–0.0842 in)
Valve face width B (exhaust) 1.538–2.138 mm (0.0606–0.0842 in)
Valve seat width C (intake) 0.90–1.10 mm (0.0354–0.0433 in)
Limit 1.6 mm (0.06 in)
Valve seat width C (exhaust) 0.90–1.10 mm (0.0354–0.0433 in)
Limit 1.6 mm (0.06 in)
Valve margin thickness D (intake) 0.50–0.90 mm (0.0197–0.0354 in)
Valve margin thickness D (exhaust) 0.50–0.90 mm (0.0197–0.0354 in)
Valve stem diameter (intake) 4.475–4.490 mm (0.1762–0.1768 in)
Limit 4.445 mm (0.1750 in)
Valve stem diameter (exhaust) 4.460–4.475 mm (0.1756–0.1762 in)
Limit 4.430 mm (0.1744 in)
Valve guide inside diameter (intake) 4.500–4.512 mm (0.1772–0.1776 in)
Limit 4.550 mm (0.1791 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)
A
B
C
D