1999 Ski-Doo Factory Shop Manual Volume Two, Page 258Get this manual
Section 06 ELECTRICAL Subsection 02 (IGNITION TIMING)
NIPPONDENSO TRIGGER COIL SYSTEM
494, 583, and 670 Engine Types Ignition timing is adjusted by movement of trigger coilOn 583 engine raising position of trigger coil retards ignitionLowering position of trigger advances ignitionOn 494 and 670 engines, moving trigger coil to right retards ignition and moving to left advances ignition-
CAUTION