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question about CDI

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I have a question about something I noticed on my friend's KLR650's ignition system last night while we were fixing a faulty relay.

I noticed the the CDI box required an input from the starting circuit. It wanted to know "when" the system was "cranking".

In a conventional Kettering ( points ) ignition system, the reduced battery voltage available from the starter draw required that the "ballast" resistor hooked up inline with the ignition coil be switched OUT of the circuit. In other words, while starting, the system would feed the FULL available battery voltage, whatever it was, to the coil.

After the starter was disengaged, the ballast resistor would be placed back into the circuit, and the ignition coil would receive <12 volts, maybe 6 or 7 for normal operation.

Now, I SUPPOSE, a CDI system could need the same arrangement for the charging of the ignition capacitor; after all, reduced voltage would change the charge time of said capacitor?

I havn't looked at any CDI schematics; I was wondering if someone could tell me if this is the case.

What exactly is the CDI box altering in its behavior during the cranking of the engine? Maybe it's something completely different, the timing of the spark or something?

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It's probably retarding the timing to ease the stress on everything. Too bad Kitaco can't figure this out.:busted:

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The other thing I gather from reading the all knowing 'net, is that it might be issuing "multiple" sparks during the cranking, since the short duration single spark it normally issues makes it "difficult" for an engine to start ....

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