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Discussion Starter · #1 ·
So, I have a 1980 cb400t Hawk that I bought as a project. It ran when I first started to work on it. It had been sitting for years, so I took a bunch of things apart for cleaning, greasing, repair, etc.

When I put everything back together and went to start it, it cranked nicely a few times but I had failed to properly secure the ground wire to the frame. When it cranked those few times, the wire jostled and there were a few sparks that flew from where the wire was contacting the frame. I stopped cranking the engine, secured the wire and now I get nothing.

My experience with electronic ignition systems is that a mistake like this tends to fry the electronic control systems on the vehicle (I made a similar mistake once on and electronic ignition/EFi car and had to replace the ECU computer). I have tested the coil and starter motor and they're both fine.

I just wanted to ask you all if my assumption that I need to replace my cdi unit is correct or if there are other things that I should check first. ...This is my first bike with electronic ignition...
 

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By nothing, are you saying it won't crank? Even if you did damage the igniter, the engine should still crank; check your fuses or breaker. If it cranks, but won't fire, put a spare spark plug in one of the wires and see if it is getting spark.
 

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Discussion Starter · #3 ·
I mean nothing whatsoever. No lights, no starter, no nothing. The fuses are good. I guess I wasn't really thinking this through correctly. I guess it boils down to hoping that motorcycle cdi's incorporated some sort of main relay.

The battery, fuses, starter and coil all seem to be good. But, as an apparent result of the aforementioned sparking, nothing happens when I turn on the key. The only reason that I could think of that this might be the case was some sort of relay or something incorporated into the cdi. Is there anything else you can think of to check?

Thanks!
 

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No relays; the key switch is what sends the power to everything. There probably is a master fuse between the battery and the key switch; after that, connections from the battery to the switch and to ground would be suspect. Wiring that old could be brittle, so yoy may have snapped the wires inside the insulation without knowing. You'll need a voltmeter to find out where the power stops.
 

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There is a 30A fuse between the positive post on the starter solenoid and the battery. These are usually a "dog bone" metal strip. If you have nothing as you've described, this fuse is blown. Replace and everything should get power.
 
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