2004 Skidoo ZX Series Service Manual, Page 158Get this manual
Section 04 ENGINES (2-STROKE) Subsection 03 (ENGINE LEAK TEST AND MEASUREMENT)
RING END GAP
Position ring half-way between transfer ports and intake portNOTE: In order to correctly position the ring in the cylinder, use piston as pusherUsing feeler gauge, check ring end gapReplace ring if gap exceeds specified toleranceRefer to TECHNICAL DATA1 A
F01D0KA
1Measuring perpendicularly (90) to piston pin axis A16 mm (58 in)
Read the measurement on the cylinder bore gaugeThe result is the exact pistoncylinder wall clearanceIf clearance exceeds specified tolerance, replace cylinder or rebore and install oversize piston depending on engine typeRefer to TECHNICAL DATANOTE: Make sure the cylinder bore gauge indicator is set exactly at the same position as with the micrometer, otherwise the reading will be falseIMPORTANT: The total pistoncylinder clearance (actual cylinder diameter minus actual piston skirt diameter) should be within 0.30 mm (.012 in)