Author Topic: I can't figure out this CDI relay for some reason. Any 12v friendly folks?  (Read 11078 times)

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Offline jauzon22

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So I've hit a stopping point with the starter circuit. I knew going into it the CDI would be funky, but I couldn't seem to figure out a configuration to get the starter motor moving. I did my best with a crudely drawn diagram of the current setup. At first I thought it was something with the neutral wire so I currently have that grounded out during the testing phase.

If I understand what the Revival cycles guys are telling me, the problem lies in how I have the relay wired from ignition to the run/kill start circuit.

There is a black/white wire coming out of the handlebar controls that I noticed is not wired into my setup right now but I have that black/white wire coming out of the cdi as the tapped into wire OUT of the relay for ignition (87a?).

How would the 5 prong relay be wired to the handlebar for the kill switch control? Do I have the starter solenoid in the wrong position (I think there should be a negative from m unit to solenoid right, idk)? 
1982 Honda CM450C

Online scottly

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The white/black wire from the CDI is open when the key is on, or the handlebar kill switch is set to "run", and connected to ground when the key is off, or the handlebar kill switch is set to either "off" position. This wire should be connected to relay post 87a, and post 30 should be connected to ground, along with post 85. Post 86 should go to the m-unit or the keyswitch, so that it has 12V when the key is on, operating the relay and removing the ground from the white/black wire.
The handlebar kill switch has a green ground wire along with the white/black wire. The green wire should be grounded, and the white/black should connect to the same white/black that runs from the CDI to the relay, so that either condition kills the motor.
The starter is a separate circuit. Are you using the neutral switch-clutch switch safety system? If so, that's where the ground comes from for the solenoid: the starter will only operate with the trans in neutral and/or with the clutch pulled in.
« Last Edit: July 17, 2025, 05:48:37 PM by scottly »
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