2007 Polaris Two Stroke Snowmobile Workshop Repair manual, Page 58Get this manual
MAINTENANCE INSPECTONS
Cylinder Head Inspection Cylinder Measurement Worksheet
Taper limitTyBy and TxBx Cylinder taper limit is .002"(.051mm) Max Cylinder out of round limit is .002"(.051mm)
Inspect each piston dome area of the cylinder head for warping by placing straight edge across the dome areaWith feeler gauge measure any gap under the straight edgeReplace cylinder head if measurement exceeds the service limit of .003" (.08mm)NOTE: Cylinder .003"(.08mm)head warp service limit is:
Cylinder Honing
The cylinder bore must be de-glazed whenever new piston rings are installedA light honing with fine stones removes only very small amount of materialA proper crosshatch pattern is important to provide surface that will hold oil, and allow the rings to seat properlyIf the crosshatch is too steep, oil retention will be reducedA crosshatch angle which is too shallow will cause ring vibration, poor sealing, and overheating of the rings due to blow-by and reduced contact with the cylinder wallService life of the pistons and rings will be greatly reducedNOTE: Nikasil cylinder can be lightly honed with soft stone hone but an not be oversized