1999 Ski-Doo Factory Shop Manual Volume One, Page 233Get this manual
Section 05 TRANSMISSION Subsection 07 (CHAINCASE)
REMOVAL
To remove chaincase proceed as followsRemove tuned exhaust pipe and muffler
INSPECTION
Visually inspect the chain for cracked, damaged or missing linksCheck for worn or defective bearings, sprockets and chain tensioner components;
WARNING
Never remove exhaust components when engine is hotRemove hair pin no8Release drive chain tension by unscrewing tensioner adjustment screwDrain oil by removing chaincase cover no2Remove cotter pin no3, nut no4, washer no26 retaining upper sprocket no5 and screw no15 retaining lower sprocket no16Pull sprockets and drive chain simultaneouslyRemove shims nos6 and 17NOTE: Should countershaft removal be required, refer to BRAKE 05-06 then look for Brake discRemove nuts no14Three nuts are behind the lower sprocket
WARNING
If chain deflection is greater than 38 mm (1.5 in) (without chain tensioner), replace chain and check condition of sprockets
GEAR RATIO MODIFICATION
For particular applications, the number of teeth of the sprockets can be increased or decreased on lower and upper sprocketsRefer to TECHNICAL DATA 10 for gear ratios