Magneto Power

Fabian

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Call me an idiot for asking this question, but does the standard Happy Time style magneto have enough power to run "two" CDI's and naturally "two" sparkplugs?

Fabian
 
Interesting thought. My approach would be to unwind both the white and blue winding, counting the number of turns on the blue one. Purchase enough magnet wire of the same size as the blue, and make two CDI windings.

Then there would be the problem of drilling and tapping for a second sparkplug... Likely a job for a machine shop.
 
Why would you want to add a 2nd plug to 1 cylinder.

I don't think it would gain anything.
 
Flapdoodle,

You must be psychic as you're obviously reading my mind.
The notion of running CDI and sparkplug redundancy has always been on my mind, not to mention more consistant combustion, just like the Rotax 2-stroke 582 aero engines.

A side benefit, is to be able to run two sparkplugs with slightly different heat ranges.
This would be quite handy with the jetting i'm currently running.

Fabian
 
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So, how much energy is required to run two sparkplugs and CDI's and how much energy is the standard magneto capable of producing?

Fabian
 
A side benefit, is to be able to run two sparkplugs with slightly different heat ranges.
This would be quite handy with the jetting i'm currently running.

That would do as long as one plug was not so hot as to cause detonation, but then the compression ratio on an HT may be so low that detonation isn't possible.

An experiment could be done... Try a second CDI wired to the original coil with a sparkplug dangling from it. There is a slight chance that the original coil could handle two CDI.
 
The original coil barly handles 1 plug.

I think it wouldnt do anything.

It would have too low of a charge.
 
The original coil barly handles 1 plug.

I think it wouldnt do anything.

It would have too low of a charge.

After a brisk 2 mile ride to warm the engine, I connected a second CDI.
The idle slowly dropped a little I guess because of the added load, but then it settled nicely. The idle was as smooth as it has always been. Disconnecting the second CDI made the idle speed up again to where it was.

Why do you say it "barly" handles 1 plug?
 
The early Yamaha DT250 had a 2nd "backup" plug. In those days plug fouling was common.

These with days modern plugs and oils its not required.

Even if you could get 2 CDI's running in parallel of one or even two coils I doubt the timing would be the same given the quality of these parts.

Two plugs in series might work,with really small gaps though.

Twin spark engines work well when there is a large bore for the 2 flame fronts generated.

In a bore less than 100mm one spark is enough i think.
 
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