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Discussion Starter · #1 ·
I finally obtained the correct Neiman key for my Ipotessi 350 ignition. This allowed me to take the barrel out of the top yoke. I mended some frayed and worn leads and connected it all back together. I have no power through the red lead from the ignition switch to the coils and beyond. I have checked for continuity and everything is good. The cdi box is good. Any clues please? Even if the dansi electronic ignition is broken there should still be current to the coils when the key is turned
 

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Old Wing Nut
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I do believe that is magneto ignition. No current unless the engine is turning over, rotor spinning around stator coils.. Have you checked for voltage whilst kicking the starter? May need a peak voltage meter or RMS meter to measure.

Early CDI systems are not battery powered.
 

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Discussion Starter · #3 ·
I have checked for a spark whilst kicking the starter and there Is none. Where do I check for voltage?
 

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Old Wing Nut
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In Capacitor Discharge Ignition systems the CDI unit sends a voltage spike to the coil. It is basically a large capacitor rapidly discharging into the ignition coil primary winding. That sudden voltage pulse in the primary windings of the coil creates an expanding magnetic field which induces a larger voltage in the secondary coil windings which then finds ground by jumping the gap at the spark plug electrode.

Using a peak reading voltmeter you should be able to measure that pulse of electricity when the capacitor discharges.

The CDI unit has circuitry that gets a charge voltage from the magneto to "load" the capacitor, and a signal voltage that tells it where the crankshaft rotation is and when to make a spark (unload the capacitor into the ignition coil).

The first test would be to measure the voltages coming from the charge and pulse (trigger) coils in the magneto going to the CDI box. you can also measure their resistance and insulation. Of course it helps to have specifications for that. Not sure if there is a manual for your bike that gives that information.
If the magneto isn't providing the proper signals to the box then the box can't work.

You should also measure resistance of the ignition coil's primary and secondary windings to see if they are in spec, too. Again, the spec may be hard to find if the manual doesn't provide it.

Diagnosis of most CDI systems involves testing everything around the CDI unit first as the CDI unit itself is usually not able to be tested.
I hope you can sort it out.
 
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