1971-1973 Arctic Cat Snowmobiles Factory Service Manual, Page 50Get this manual
ENGINE SERVICING (TVVIN CYLINDER) Timing (Twin Cylinder)
1Disconnect the spark plug lead wires and remove the spark plugs from the cylinder headsDisassemble the recoil starter from the engine by removing the three (3) bolts and lock washersRotate the crankshaft 180 or until the set of points on the right are in fully-open positionAdjust the points from .012" to .016", using screwdriver and feeler gaugeNOTE: Adjusting point gap changes the ignition timing on only one cylinderConversely, adjusting the stator plate changes the "0;"00 tirninq of both cylinders2Remove the auxiliary starting pulley from the magneto ring plate, using the holding tool (Arctic Part No0144-007)The axial fan drive pulley must now be removedAfter the points are secured in position, recheck the point gap; tightening of the screw may have altered the point gapCheck the timing, using continuity light in conjunction with the Timing Mark Method (see step 10) or the Dial Indicator Method (see step 11)TIMING MARK METHOD