Cylinder Head

Cylinder Head:
Combustion Chamber Volume 46.34 - 48.34 cc
Gasket Surface Flatness 0.003 In Any 6 inches - 0.006 Overall
Gasket Surface Finish (RMS) 60 - 150

Rocker Arm:
Shaft Diameter 0.7799 - 0.7811
Bore Diameter 0.7830 - 0.7842
Ratio 1.46:1
Push Rod Runout:
T.I.R Max. 0.020

Valve Guide:
Valve Guide Bore Diameter 0.3174 - 0.3184

Valve Seats:
Width:
Intake 0.060 - 0.079
Exhaust 0.060 - 0.079
Angle 45°
Runout Limit (T.I.R.) 0.0015 Max.

Valve Springs:
Compression Pressure:
60.0 - 68.0 lbs. @ 1.585
138.0 - 149.0 @ 1.222
Free Length:
Approximate 1.91
Assembled Height 1-37/64-1-39/64
Service Limit 10% Pressure Loss @ Specified Length
Out of Square Service Limit 5/64 (0.078)

Valves:
Valve Stem To Guide Clearance:
Intake 0.0008 - 0.0025
Exhaust 0.0018 - 0.0035
Service Clearance 0.0055
Valve Head Diameter:
Intake 43.5 mm (1.71 inch)
Exhaust 34.5 mm (1.36 inch)
Valve Face Runout Limit 0.002 Max.
Valve Face Angle 44°
Valve Stem Diameter:
Standard:
Intake 0.3159 - 0.3167
Exhaust 0.3149 - 0.3235
0.008 Oversize:
Intake 0.3239 - 0.3245
Exhaust 0.3228 - 0.3235
0.016 Oversize:
Intake 0.3318 - 0.3324
Exhaust 0.3307 - 0.3314