1974 Ski-Doo Shop Manual, Page 235Get this manual
TWO CYLINDER ENGINE TECHNICAL DATA Nominal dimension of cylinder bore ENGINE TYPE -'"
Cylinder out of round
Measuring Y2" (13 mm) from top of cylinder with cyl inder gauge, check if the cylinder out of round is more than .002" (0.05 mm)If larger, cylinder should be rebored and honed or should be replaced
STANDARD
OVERSIZE
248 294 305 338 343 346 396 401 434 436 440 640
2.1260" 2.2441" 2.1850" 2.3425" 2.3425" 2.3425" 2.5394" 2.5394" 2.6575" 2.6575" 2.6575" 2.9921"