1985 Ski-Doo snowmobile Service Manual, Page 203Get this manual
Section 02 ENGINE Sub-section 10 (ENGINE DIMENSIONS MEASUREMENT)
Measurement To determine piston to wall clearance, the piston should be measured right under the axis hole and the cylinder should be measured 16 mm (5,8" below its top edge
NOTE: Ringpiston groove clearance can be measured only on rectangular ring
AOO1002025
RING ENG GAP
ENGINE TYPE All 1985 engines NEW RING MINIMUM-MAXIMUM 0.200.35 mm (008.014") WEAR LIMIT 1.0 mm (039")
Position ring half way between transfer ports and intake portOn rotary valve engines, position ring just below transfer portsAOO1002024