Yamaha G1 Charge Coil questions

[Contrary1]

B/W goes to ground in the off position but is an open circuit in Forward and Reverse

Black goes to ground in all positions (although resistance is 1.7 ohms to ground in the reverse position compared to 0.2 ohms in off and forward).

Swapped W/R and W/G. After swapping them, it still did NOT have spark in reverse but it still had spark in forward.

[1989Marathon]

Put the W/G and W/R wires back to stock. Disconnect the back-up buzzer and try again.

[Contrary1]

Back to stock minus the buzzer.
B/W goes to ground only in the off position.

Black goes to gound in all position (0.1 ohms in all positions).

Still no spark in reverse (interestingly the timing light showed about 5 sparks and then nothing and I could not get it to duplicate it).

Just out of curiosity, I reveresed the W/R and W/G again to see if it changed. The results were the same. Spark in forward and nothing in reverse. So I put it back to stock.

[1989Marathon]

If you check AC voltage between the Brown Magneto wire and battery ground, does it produce the same voltage in FWD and REV?

[Contrary1]

I get 13.0~13.5 volts in forward

I'm only getting 3.5~4.5 volts in reverse

[1989Marathon]

Disconnect the brown wire at the magneto and the CDI. Install a jumper between the magneto brown and CDI brown. This will eliminate the stock wire to see if it is shorted somehow in reverse.

[Contrary1]

Disconnected the brown wire from the Mag and the CDI unit and installed a bypass jumper. No change. Still no spark in reverse and the voltage in reverse with the bypass installed was still only around 4.5 volts AC.

I'm assuming the low voltage in reverse is prohibiting the generation of a spark from the ignition coil.

[1989Marathon]

Yes. Same setup. Disconnect the Black wire from the Magneto and run another jumper from the Magneto Black wire, straight to battery ground. Check voltage again.

[Contrary1]

Will have to try that tomorrow as we have a lines of storms rolling in and are about to get very wet along with an excellent lightning show.

[1989Marathon]

OK. Good luck. and keep us posted please. I have a feeling the ground to the charging coil is bad, and only shows up in reverse. Installing a jumper to the black wire will prove that out.