120 – Timing Twin Motors

TIMING TWIN MOTORS

When servicing oil pumps on battery ignition motors or primary drive and transmission on 45 magneto ignition motors, it becomes necessary to retime ignition.

To aid in the retiming of motors, a mark is stamped on the left flywheel. This mark is a straight vertical line (I)
which appears in the center of the top oil level screw hole in the left crankcase. This mark is not too pronounced
and a good light at the screw hole is necessary.

1. Remove the top oil lever screw and spark plugs from motor.
2. Turn over motor until rear cylinder inlet valve opens and closes with exhaust valve also closed and both tappets free. Then turn motor until front cylinder exhaust valve starts to open.
3. After both rear cylinder valves are closed and front cylinder exhaust valve is opening, watch for flywheel marks.
4. When the mark appears in oil level hole, the rear piston is coming up on compression stroke and by setting points so that they are just breaking with full advanced spark, the motor will be set at original factory timing.

Magneto equipped 45 Sport Scout motors are timed as described above, however, the magneto must be timed to the motor.

After primary three row chains and magneto mounting is in place, the magneto gear must be set with the mark which
appears on the magneto gear and the mark located at the second screw boss on the front of the magneto gear housing matching. If the flywheel mark is showing and the magneto gear mark set with the mark on the magneto housing, the motor is properly timed.

INDIAN MOTOCYCLE COMPANY