I have an old motorcycle which I would like to fit with a modern CDI ignition. The ignition would be of the type typically fitted to dirt bikes and which require a high voltage AC source. They have a permanent magnet alternator with a separate high voltage stator for the ignition in addition to a 12V stator. My bike has a permanent magnet alternator which contains two 6V stators wired in parallel.
I am wondering if it is possible to use a transformer to provide a ~300V source from the stock alternator to power the CDI. I could dedicate one of the stators to the ignition if necessary. Is providing the high voltage supply as simple as this or am I missing something? Is there any specific type of transformer or characteristics/features I would need?
be more specific for fuck's sake
the transformer idea sucks. you'd be re-creating all the things that were wrong with E.T. ignition. if you're going that way you should rewind the stator.
and how is your CDI module gonna figure out the spark timing? even the chinese pitbike ignitions need a pulse coil input, are you going to weld a trigger blob onto your flywheel?
It's a 1965 Ducati 250.
I am hoping to avoid rewinding the stator because it would require a lot of turns to get the voltage I need and as the old magnets aren't as powerful as they were 50 years ago, I can't be sure what voltage I will be getting out of it. With the transformer approach I can afford to experiment.
The trigger problem is easy to solve, the high voltage supply is not.
costs about ten bux to get a flywheel remagnetised.
have you thought about a DC CDI like the ooracing shotgun? 12V and pulse coil in, spark out. £50. it would save a lot of fucking-about.
getting 12V from the stator is a matter of fitting a different regulator. typically the voltage coming out of the stator hovers around 30VAC and the reg/rec pulls it down to working voltage.
>costs about ten bux to get a flywheel remagnetised.
I'll look into this.
I had not heard of these before. I was looking at $300+ units which would be too expensive for me.
On the Ducati, you can rewire the stators in series rather than in parallel to get 12V at a lower RPM with a 12V regulator.