1972 Ski-Doo Shop Manual, Page 180Get this manual
CLEANINGINSPECTION
Dimension of Cylinder BoreThe pis ton (s) and rings must be replaced when re-boring and honing the cylinders(b) OUT OF ROUNDMeasuring 12 inch below the top of cylinder, check if the cylinder bore is out of round more than .002 inch (see fig2-8-3)If the out of round exceeds this tolerance the cylinder should be rebored and honed or replacedThe piston(s) and rings must also be replaced after re-boring and honing(c) CYLINDER TAPERMeasuring verti cally from below the intake port to 58 inch from top of the cylinder, check if taper is off more than .003 inch (fig2-8-4)Should the taper exceed this tolerance, re-bore and hone or replace cylinderAlways replace piston(s) and rings if cylinder requires re-bore and honingCAUT ION: On all two cylinder engines, the specifications of one cylinder must meet the same specifications on the other