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Engine Specifications

GENERAL SPECIFICATIONS

Year Displ. Carburetor HP at RPM Torque (Ft. Lbs. at RPM) Compr. Ratio Bore Stroke
cu. ins. cc in. mm in. mm
1977 91.0 1493 1x1-Bbl. ..... ..... 7.5-1 2.9 73.7 3.44 87.5
VALVES

Engine & Valve Head Diam. In. (mm) Face Angle Seat Angle Seat Width In. (mm) Stem Diameter In. (mm) Stem Clearance In. (mm) Valve Lift In. (mm)
1493 cc              
  Int. 1.380 45° 45.5° ..... .3107-.3113 .0007-.0023 .....
(34.99) (7.89-7.91) (.02-.06)
Exh. 1.170 45° 45.5° ..... .3100-.3105 .0015-.0030 .....
(29.71) (7.874-7.887) (.04-.07)
PISTONS, PINS, RINGS

Engine PISTONS PINS RINGS
Clearance in. (mm) Piston Fit in. (mm) Rod Fit in. (mm) Rings End Gap In. (mm) Side Clearance In. (mm)
1493 cc (1).002-.003 (3) (4) 1 .012-.022 .0015-.0035
(.051-.076) (.305-.559) (.038-.089)
(2).0002-.0016 2 .012-.022 .0015-.0035
(.005-.041) (.305-.559) (.038-.089)
Oil .015-.055 .....
(.38-.1.40)
(1) At top of skirt.
(2) At bottom of skirt.
(3) Hand push fit.
(4) Interference fit.
CRANKSHAFT MAIN & CONNECTING ROD BEARINGS

Engine MAIN BEARINGS CONNECTING ROD BEARINGS
Journal Diam. In. (mm) Clearance In. (mm) Thrust Bearing Crankshaft End Play In. (mm) Journal Diam. In. (mm) Clearance In. (mm) Side Play In. (mm)
1493 cc 2.3115-2.3120 .0005-.002 Rear .006-.014 1.8750-1.8755 .001-.003 .....
(58.713-58.725) (.013-.050) (.15-.36) (47.625-47.638) (.03-.08)
VALVE SPRINGS

Engine Free Length In. (mm) PRESSURE (LBS.)
Valve Closed Valve Open
1493 cc 1.52 ..... .....
(38.6)
CAMSHAFT

Engine Journal Diam. in. (mm) Clearance in. (mm) Lobe Lift in. (mm)
1493 cc      
  No. 1 1.9659-1.9664 .0016-.0036 .....
(49.93-49.95) (.04-.09)
No. 2 1.9649-1.9654 .0026-.0046 .....
(49.90-49.92) (.07-.12)
No. 3 1.9659-1.9664 .0016-.0036 .....
(49.93-49.95) (.04-.09)
VALVE TIMING

Engine INTAKE EXHAUST
Open (BTDC) Close (ALDC) Open (BLDC) Close (ATDC)
1493 cc 18° 58° 58° 18°
TIGHTENING SPECIFICATIONS

Application Ft. Lbs. (mkg)
Cylinder Head 46 (6.4)
Connecting Rod Bolt 40-45 (5.5-6.2)
Rocker Shaft 32 (4.4)
Oil Pan 20 (2.8)
Engine Front Cover
  Small Bolt 10 (1.4)
Large Bolt 20 (2.8)
Water Pump 20 (2.8)
Manifold 25 (3.5)
Crankshaft Pulley 150 (20.7)
Rocker Cover 2 (.03)
Main Bearing Cap Bolts 65 (9.0)