Specs for Yamaha models G1
Standard Bore: 68.00 mm
Piston Clearance: 0.03 - 0.035
mm
Ring End Gap: 0.2 - 0.4 mm
Head Bolts: (Initial) 14.5 ft. lbs. (Final)
18 ft. lbs.
Crankcase Bolts: 4.7 ft.
lbs
Flywheel Nut: 52.6 ft. lbs.
Clutch Bolt: 43 ft.
lbs.
Specs for Yamaha models G2, G8 & G9
Engines
Standard Bore: 73.00
mm
Piston Clearance: 0.03 - 0.05 mm
Ring End Gap: 0.2 - 0.4 mm
Intake
Valve (Cold): 0.1 mm
Exhaust Valve(Cold): 0.1mm
Head Bolts: 20 ft. lbs.
Connecting Rod Cap: 29 ft.
lbs.
Crankcase Bolts: 17 ft.
lbs.
Flywheel Nut: 54 ft. lbs.
Clutch Bolt: 54
ft. lbs.
Oil Drain Plug: 22 ft. lbs.
Specs for Yamaha G14, G16, G19, G20 & G21
Engines
Standard Bore: 78.00
mm
Piston Clearance: .03 - .05mm
Ring End Gap: 0.2 - 0.4 mm
Intake
Valve (Cold): 0.1mm
Exhaust Valve(Cold): 0.1mm
Cylinder Head: 36 ft. lbs.
Connecting Rod
Cap: 14 ft. lbs.
Crankcase: (8mm) 19 ft. lbs. (10mm) 27 ft.
lbs.
Flywheel Nut: 54 ft. lbs.
Clutch Bolt: 75 ft. lbs.
Oil Drain
Plug: 22 ft. lbs.