2005 Ski-Doo Racing Handbook, Page 240Get this manual
SECTION 05ENGINE PREPARATION
RINGPISTON GROOVE CLEARANCE
Using feeler gauge check clearance between rectangular ring and grooveReplace piston if clearance exceeds specified toleranceRefer to TECHNICAL DATA
Measuring (in crankcase) First, check deflection with crankshaft in crankcaseIf deflection exceeds the specified tolerance, recheck deflection using V-shaped blocks to determine the defective part(s)See belowMeasuring (on bench) Once engine is disassembled, check crankshaft deflection on V-shaped blocksIf deflection exceeds the specified tolerance, it can be worn bearings or bent crankshaftRemove crankshaft bearings and check deflection again on V-shaped blocks to determine the defective part(s)See measurement in following illustration