1985 Ski-Doo snowmobile Service Manual, Page 240Get this manual
Section 03 TRANSMISSION Sub-section 02 (DRIVE BELT)
Skandic 377R, Formula MX, Plus
Check if pulley distance is according to specifications If not, adjust as follows Skandic 377R: Slack the four (41 chaincase retaining nuts and the countershaft support lock nutRemove the clevis pin and screw or unscrew the adjusting bracket to adjust distance between pulleys
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Alpine model
Lock nut
The deflection IS adjusted by moving engine bracketTo do so, loosen engine bracket nuts and adjust distance between pulleys
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