Coil Replacement

[MarkAkerman]

Do I need to change the ignition coil to a 12 volt if I am converting from a 6 volt to 12 volt system? I'm keeping the 6 volt starter.

[Jim Becker]

You can either change to a 12-volt coil or continue to use the 6-volt coil by putting a ballast resistor in series with the coil to drop the voltage at the coil. You can find lots of prior discussion of this question by doing a search for "ballast resistor" using the search field at the top of this page. Here is a recent one that comes up that way and covers the topic pretty well:
viewtopic.php?f=1&t=108248&p=858833&hilit=ballast+resistor#p858833

[MarkAkerman]

Thanks Jim!