Motogadget did not factor in technology for installing a CDI ignition meaning a work around is necessary. The method we've developed keeps the ignition system integrated with the m-Unit and allows you to use the m-Units kill switch.
What exactly is a CDI?
The acronym CDI has become a catch all term for any black ignition module but stands for Capacitive Discharge Ignition, and a true CDI ignition module is fundamentally different than any other ignition module and as such it operates at a different voltage than the rest of the electrical system and is frequently self excited, which means it will run without any battery in the bike. These are most common on off road bikes, and a few of the smaller Japanese bikes from the 80’s and 90’s.
How do I determine if I have a CDI?
If the coils do not have a connection to 12v+ it is a good indication that it is a CDI system. But I find the easiest way is to look at your OEM wiring diagram and locate the kill switch. Once you've found it trace each wire leading away from it, there will likely be two. One of them will go to the ignition module the other wire will go to ground. The ground is the key, When the kill switch is activated it completes a circuit that grounds out the CDI killing the ignition spark.
In other types of ignitions the OEM kill switch when activated will break the 12v+ power circuit to the ignition system cutting ignition spark.
The Revival Solution
If you think about how the m-Unit outputs work it becomes clear why a CDI will not work here, the Ignition Out provides 12v+ power which the CDI does not require. But by using a common 5 pole, normally closed relay we can make this work just like any other ignition. When the m-Unit provides power to the Ignition Output the relay opens the switched circuit. When the Kill Switch is activated the m-Unit cuts power to the relay inturn closing the switched circuit, grounding the CDI and eliminating ignition spark.
We offer a quality Hella Waterproof Relay perfect for this application on our site.
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