Coil selection

[dxhall]

I’m working on the wiring to my project Aermacchi / Harley.  Mostly because I want to run an electronic tach, and also because I want to use a micro-sized battery, I need to  convert the old electrical system to 12 volts.

My idea is to wire the stock 6v generator to the stock regulator, and wire the regulator to a 6- to 12v converter, and the converter to the battery.  That seems simple enough.

The thing I haven’t yet figured out is what coil I need, or whether any 12v coil will work.  With breaker-point ignition and no fuel injection, does it matter what coil I use?

I have way too much money and time into this bike, although it is kind of cool in a strange way.  I hope it doesn’t turn out to be a total dog.

[Tom H]

If your feeding the coil 12V, then any 3ohm internal resistance automotive coil should work. Think Bosch Blue, but any decent one from you local auto parts store should be fine. I would stay away from oil filled cols if you can.

Tom

[moto-uno]

  I'd be curious what actual amperage may be available if your idea of using a transformer works out .
  I worked on the 350 Aermacchis' when they were new , and they were rather lame performing even then .
  With enough money they got fast , but how much more money do you want to spend ?  Peter