1970-1973 Ski-Doo Snowmobiles Technical Data Manual, Page 32Get this manual
NOMINAL DIMENSION OF CYLINDER BORE 1970-71-72-73 MODELS TABLE Engine Type 290 300 335 340 400 401 401 401 640 640 641 775 247 292 302 337 342 401 401 401 401 435 G40 640 640 641 775 Vehicle Models Year NOMINAL DIMENSION OF CYLINDER BORE Standard mm 75.0 76.0 78.0 78.0 64.5 64.5 64.5 64.5 76.0 76.0 76.0 82.0 69.0 75.0 76.0 78.0 78.0 64.5 64.5 64.5 64.5 67.5 76.0 76.0 76.0 76.0 82.0 inches 2.952 2.992 3.070 3.070 2.539 2.539 2.539 2.539 2.992 2.992 2.992 3.228 2.716 2.952 2.992 3.070 3.070 2.539 2.539 2.539 2.539 2.657 2.992 2.992 2.992 2.992 3.228 1st Oversize mm 75.5 76.5 78'!) 78.5 65.0 65.0 65.0 65.0 76.5 76.5 76.5 82.5 69.5 75.5 76.5 78.5 78.5 65.0 65.0 65.0 65.0 68.0 76.5 76.5 76.5 76.5 82.5 inches 2.972 3.011 3.090 3.090 2.559 2.559 2.559 2.559 3.011 3.011 3.011 3.248 2.736 2.972 3.011 3.090 3.090 2.559 2.559 2.559 2.559 2.677 3.011 3.011 3.011 3.011 3.248 2nd Oversize mm inches 3rd Oversize mm inches 4th Oversize mm inches