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Anyone know how CDI works?

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ITS bugging me i does anyone know how CDI ignition works. Ive got an idea but i wanna know exactly how it works. ive been looking all over the internet to see if theres a good explanation but i cant find one

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PM Eddie Sisneros and ask him to post the answer here. He knows. He has designed a mappable CDI unit for the DRZ that I'm looking forward to getting.

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http://www.answers.com/topic/capacitor-discharge-ignition

This kind of explains it. Do you know what a capacitor does?

http://electronics.howstuffworks.com/capacitor.htm

You also need to know what transformers and diodes do. If you do a search on howstuffworks.com you will find how they work, but all you really need to know is that a transformer can "step up" voltage. For example in a typical small engine, you start with say 12V. A transformer will step up that voltage to around 30-40 kilovolts (1kilovolt=1000volts). 12V wont travel through air (gap at spark plug), but 40kV will. A diode is like a one way valve. It only allows electric current to flow one way.

Now to put it all together, the voltage is stepped up at the transformer, and put through the diode into the capacitor. When the connection is made between the capacitor and the wire to the spark plug, it arcs across the gap in the plug. Then the connection is broken and the cap is charged again. The diode is there so no current flows back toward the transformer, discharging the capacitor in the wrong direction.

I don't know your electrical background (so sorry if this seems elementary), but you know when you shock your friends with static after dragging your shoes across the carpet? There can be thousands of volts in that discharge. This is similar to the spark plug idea.

Are you totally confused yet? I couldn't find a good illustration, but if you search long enough, you might find one.

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