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Discussion Starter #1
82GL500

Rebuilt the wiring harness for a cafe project and now only getting spark doing the Ignition Pickup Simulation Test. Everything checked ok with coil resistance test. Bike was running perfect before starting the project and never opened the motor. Just gave it a paint job. Could the problem be something other than the ignition timing pick up coils or mechanical timing advance unit?
 

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Did you include the ground wire that is just in front of the left coil when you rewired the bike???
 

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Yes. Consolidated everything to 1 ground.
On my GL500 there was a ground wire that attached under the seat. While everything else would work correctly, without that ground wire connected, the bike would not fire or run (even though the spark plugs would fire when the motor was turned over. My bike was starting and running fine until I cut the tail off (and disconnected that ground wire), then it would turn over, but only seem to barely try to fire on one side. Once I grounded that terminal, she fired right up.

Main Fuse and Grounding

The 2nd and 3rd pics are the wire(s) I am referring to.
 

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I assumed that wire was for the accessories, as the bike would crank over, and you'd hear one cylinder try to fire along with the occasional backfire. Being that was going on and when I pulled the spark plugs, they were sparking (albeit kind of weak).

If your bike is behaving the same way, I'd recommend taking another look at your stock harness (if you still have it) and double check where those two grounds go to. Its a pretty big task to build a harness from scratch and all too easy to miss one wire. Let us know what you find... and be sure to share pics... I'd like to know more about your custom harness.
 

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now only getting spark doing the Ignition Pickup Simulation Test

Since you are getting spark with this test, the issue is the ignition pickup coils and/or related wiring.

What are the results of the Timing Pickup Coil Resistance Tests?
 

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david he says the pulse gen resistance is good with no continuity to ground on and of the blues or yellows

BUT there is zero voltage pulsing with a meter set at 2 volts

so i think the atu is loose or the reluctor broken

how ever i am going to send him a gl500 wiring harness just to try

my gut says something is messed up in the harness

this motor ran before the harness was adjusted

and the rear cover has not been off
 

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Discussion Starter #13
I found the problem in my wire harness. I've got spark! I mixed up the blue and yellow wires in the connector. Once I get everything back together I'll let you know. Before I ran into the wiring problem I was struggling with routing the throttle cables. I'll send you some pics once I get the wire harness back together. Also, I'm using what I think is a 78 cx custom gas tank. Can I use a stock petcock?
 
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