System Specifications

Cylinder head gasket surface flatness 0.18 mm (0.007 inch)
Combustion chamber volume 61.5-64.5 cc
Valve guide bore diameter 7.015-7.044 mm (0.276-0.277 inch)
Valve stem diameter - intake (standard) 6.955-6.988 mm (0.2738-0.2751 inch)
Valve stem diameter - exhaust (standard) 6.929-6.962 mm (0.2728-0.2741 inch)
Valve stem diameter - intake, oversize 9.075-9.055 mm (0.3573-0.3565 inch)
Valve stem diameter - exhaust, oversize 9.063-9.043 mm (0.3568-0.3560 inch)
Valve stem diameter - intake, oversize 9.456-9.436 mm (0.3723-0.3715 inch)
Valve stem diameter - exhaust, oversize 9.444-9.424 mm (0.3718-0.3710 inch)
Valve stem-to-guide clearance - intake 0.20-0.69 mm (0.045-0.090 inch)
Valve stem-to-guide clearance - exhaust 0.038-0.083 mm (0.0015-0.0033 inch)
Valve head diameter - intake 47.27 min (0.86 inch)
Valve head diameter - exhaust 37.1 mm (1.46 inch)
Valve face runout 0.05 mm (0.002 inch)
Valve face angle 45.675 degrees
Valve seat width 1.5-2.0 mm
Valve seat runout 0.076 mm (0.003 inch)
Valve seat angle 44.75 degrees
Valve spring free length 50.5 mm (1.99 inch)
Valve spring installed height 40.7 mm (1.62 inch)
Rocker arm ratio 1.73


For torque specifications, refer to the service procedure.