Arctic Cat 660 cc, Service Manual, Page: 15 / 396

2-3
2
Engine Specifications
(120 cc)
Cylinder Bore Diameter (Max) 68.020 mm
(2.6779 in.)
Cylinder Head Distortion (Max) 0.030 mm
(0.001 in.)
Manifold Distortion (Max) 0.050 mm
(0.002 in.)
Piston Diameter
(3/4 up from skirt perpendicular to
pin)
67.970-67.990 mm
(2.6760-2.6768 in.)
Piston Skirt/Cylinder
Clearance
0.02-0.04 mm
(0.0008-0.0016 in.)
Piston Connecting Rod
Small End Bore
21.003-21.013 mm
(0.8269-0.8273 in.)
Piston Pin/Connecting Rod
Small End Clearance
0.003-0.018 mm
(0.0001-0.0007 in.)
Piston Pin Bore In Piston 21.002-21.008 mm
0.8268-0.8271 in.)
Piston Pin (Dia) 20.995-21.000 mm
(0.8266-0.8268 in.)
Piston Ring Groove/Ring
Clearance (1st)
(2nd)
(Oil)
0.04-0.08 mm
(0.0012-0.0031 in.)
0.03-0.07 mm
(0.0012-0.0028 in.)
0.06-0.15 mm
(0.0024-0.0059 in.)
Valve Guide Inside Diameter 5.500-5.512 mm
(0.2165-0.2170 in.)
Valve Head
(Thickness) (Int)
(Exh)
1.0 mm
(0.039 in.)
1.15 mm
(0.045 in.)
Valve Lash Clearance -
Cold (59°-77° F) (Int)
(Exh)
0.18-0.23 mm
(0.007-0.009 in.)
0.22-0.27 mm
(0.008-0.010 in.)
Valve Seat Width (Int)
(Exh)
1.80-2.20 mm
(0.0709-0.0866 in.)
1.65-2.05 mm
(0.0650-0.0807 in.)
Valve Stem
Diameter (Int)
(Exh)
5.465-5.480 mm
(0.2152-0.2157 in.)
5.440-5.455 mm
(0.2142-0.2148 in.)
Valve Stem/Guide
Clearance (Int)
(Exh)
0.020-0.047 mm
(0.0008-0.0019 in.)
0.045-0.072 mm
(0.0018-0.0029 in.)
Cam Lobe Height 30.20-30.56 mm
(1.189-1.203 in.)
Crank Pin Diameter 25.990-26.000 mm
(1.0232-1.0236 in.)
Crankshaft Runout (Max) 0.100 mm
(0.004 in.)
Cylinder Bore Diameter (Max) 60.25 mm
(2.372 in.)
Cylinder Head Distortion (Max) 0.03 mm
(0.0012 in.)
Piston Diameter
(14 mm up from skirt
perpendicular to pin)
59.880-59.990 mm
(2.3575-2.3618 in.)
Piston Skirt/Cylinder
Clearance
0.020-0.120 mm
(0.0008-0.0047 in.)
Piston Ring End Gap (1st & 2nd) 0.20-0.70 mm
(0.0079-0.0280 in.)
Connecting Rod Big End
Side Clearance
0.20-1.20 mm
(0.0079-0.0472 in.)
Connecting Rod Big End
Inside Diameter
26.015-26.025 mm
(1.0242-1.0246 in.)
Crank Pin/Connecting
Rod Clearance
0.015-0.070 mm
(0.0006-0.0028 in.)
Connecting Rod Small End Bore 15.006-15.030 mm
(0.5908-0.5917 in.)
Piston Pin/Connecting Rod
Small End Clearance
0.006-0.050 mm
(0.0002-0.0020 in.)
Piston Pin Bore In Piston 15.006-15.030 mm
(0.5908-0.5917 in.)
Piston Pin Diameter 14.980-14.995 mm
(0.5898-0.5904 in.)
Piston Ring Thickness (1st & 2nd) 1.47-1.49 mm
(0.058-0.059 in.)
Piston Ring Groove (1st & 2nd)
Width
(Oil)
1.52-1.54 mm
(0.060-0.061 in.)
2.51-2.53 mm
(0.098-0.099 in.)
Piston Ring Groove/Ring
Clearance (1st & 2nd) 0.030-0.010 mm
(0.0012-0.0039 in.)
Valve Guide Hole Diameter 11.200-11.218 mm
(0.4409-0.4416 in.)
Valve Guide Inside Diameter 5.500-5.512 mm
(0.2165-0.2170 in.)
Valve Stem Runout (Max) 0.05 mm
(0.002 in.)
Valve Face/Seat Width 0.8-1.0 mm
(0.032-0.039 in.)
Valve Spring Length (Max) 31.0 mm
(1.22 in.)
Valve Stem/Guide Clearance (Int)
(Max)
(Exh)
0.080 mm
(0.0031 in.)
0.100 mm
(0.0039 in.)