2005 Ski-Doo Racing Handbook, Page 393Get this manual
SECTION 082005 MX 550 AND 380 FC
GENERAL
Some drive pulley components (return spring, calibration disk) can be changed to improve vehicle performance in high altitude regionsA service bulletin will give information about calibration according to altitudeCAUTION: Such modifications should only be performed by experience mechanics since they can greatly affect vehicle performance
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WARNING
Any drive pulley repairs must be performed by an authorized Bombardier snowmobile dealerSub-component installation and assembly tolerances require strict adherence to procedures detailed
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