Coil resister

I have 3 OHM late style coils and a Dyna S. They are using too much juice for my charging system. I've read here about adding a resister but can't seem to find it. What is recommended? It's for my Z1.
Steve

That's not very common on a Z1. The problem is most often seen on a 78 or 79 Kz650 (they have 1-phase, permanent magnet charge systems).

Did you actually measure the resistance? Kz's most often came with 4 ohm coils with points, and 2.3 ohm coils with electronic ignitions. There are also some lower resistance coils that came on the earliest of the 1000's with electronic ignitions, but I'm not sure how well they are documented.

Also, coils tend to get higher in resistance as they age (but are not damaged).

You can probably use a 1 ohm, or less, resistor in line with each coil, and it should still work since the Dyna S gives a really long dwell. The resistor will have to be big. To be safe you'd probably want each to be 25 to 50 watts.

This is not the ideal situation because even though you are reducing the ignition's overall power usage, you are wasting power heating up the resistors instead of using it as spark energy. But it should still work.

You may want to look into why the charging system is not keeping up. They usually don't have a problem with the Dyna S on the 900/1000.

I have running lights, etc. I'll try the 50 watt resistors
Steve