2001 Ski-Doo Factory Shop Manual Volume One, Page 76Get this manual
Section 03 TROUBLESHOOTING Subsection 04 (TRANSMISSION AND BRAKE SYSTEMS)
SYMPTOM CONDITION TestInspection
PULLEYS DO NOT DOWN SHIFT PROPERLYNORMAL USE1Check driven pulley spring tensionaSpring tension is too weakAdjust according to specifications (refer to TECHNICAL DATA)2Refer to VIBRATIONS COMING FROM DRIVEN PULLEY and check items listed3Check drive pulley bushings (cleanliness, wear, etcaBushings stick to fixed half pulley shaftClean or replace4Check driven pulley spring tensionaSpring tension is too weakReplace