'79 XS650 Build project.

May need a diagram of that ignition circuit from ya. Ignition brand?
 
The only difference is my orange wire has a kill switch in the line, and the red/white wire runs to the M-Unit, but everything else is the same.
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Sorry to doubt you - lots of folks say CDI for anything electronic - you really do have a CDI.:)

So, I'd recommend wiring it exactly as Hugh has outlined: orange to CDI and R/W from main switch to relay as shown (no M-Unit in ignition circuit). And your pick-up gap is important too, esp. with weak spark symptom
 
I'd suggest a kill switch in series after main switch on R/W to relay too
 
So I took apart the bike and pulled the rotor to find that the stator got a bit hot. It melted the zip ties that were on it and measured out of spec for resistance. I was told this was probably the result of a bad ground on the R/R. I think I may run an extra ground wire to the R/R. The PMA produces 200W and in running all leds except the headlight, so I was thinking maybe I should put in a 50w resistor down the line, but the question is where? Between the stator and R/R or after the R/R.
I would like to get this up and running again before diving into my NU50 project. What's your hot take?
 
So I took apart the bike and pulled the rotor to find that the stator got a bit hot. It melted the zip ties that were on it and measured out of spec for resistance. I was told this was probably the result of a bad ground on the R/R. I think I may run an extra ground wire to the R/R. The PMA produces 200W and in running all leds except the headlight, so I was thinking maybe I should put in a 50w resistor down the line, but the question is where? Between the stator and R/R or after the R/R.
I would like to get this up and running again before diving into my NU50 project. What's your hot take?

Did you ever get this sorted?

Same thing happened to mine. Same setup as you - HHB CDI and M-unit.

First my regulator went bad because it wasn't grounded well enough. replaced. then started getting weak spark and the coil gave out. replaced. Everything was running well for a while then started to get weak spark again and that's when I noticed the stator looked overheated. ran it for a few more miles and then the stator finally gave out.

I'm thinking the initial damage was caused by the bad regulator ground and snowballed from there.

I'm waiting for the replacement stator and hopefully this doesn't happen again.
 
Did you ever get this sorted?

Same thing happened to mine. Same setup as you - HHB CDI and M-unit.

First my regulator went bad because it wasn't grounded well enough. replaced. then started getting weak spark and the coil gave out. replaced. Everything was running well for a while then started to get weak spark again and that's when I noticed the stator looked overheated. ran it for a few more miles and then the stator finally gave out.

I'm thinking the initial damage was caused by the bad regulator ground and snowballed from there.

I'm waiting for the replacement stator and hopefully this doesn't happen again.
I'm working with Hugh to get it sorted out, I am looking to maybe drill holes in my cover near the stator for air flow, as well as add a computer fan to blow directly onto the regulator. I also am looking to add variety of grounds to the regulator, and maybe add more lights to offset the wattage
 
Replaced the burnt stator and cleaned up all the grounds. Additionally I swapped the 30w LED headlight bulb for a 100/80w incandescent bulb. Idle voltage is now at 13ish. Previously was 14.5ish at idle. I’m hoping this is the ticket to prolonging the life of the regulator and stator!
 

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Replaced the burnt stator and cleaned up all the grounds. Additionally I swapped the 30w LED headlight bulb for a 100/80w incandescent bulb. Idle voltage is now at 13ish. Previously was 14.5ish at idle. I’m hoping this is the ticket to prolonging the life of the regulator and stator!
How long did it take to get the stator?
 
I’m in MD so like 2 days. He’s been backed up though. Best way to reach him was through FB message
I heard back from Hugh and am sending mine out tomorrow. I took the stator directly off the backing plate though to cut weight on shipping. I just received my 100/80w light bulb today, and I think that should help like it did with yours. In the mean time I'm going to establish a better ground for the reg/rect just for piece of mind. I've considered removing the side cover that sits directly over the flywheel and creating a replacement that has a scoop to direct air onto the stator for cooling. Also thought about wiring up a computer fan on top of the reg/rect.
 
Received my new stator and I went over the wires and reinforced them all with heat shrink just in case. But I did notice the ignition coil wiring is in the top left instead of bottom right, but I can't imagine that would make any difference. (No I cannot rotate it as the 3 holes are not 60° apart.) I still need to attach the connectors to the wires, and will add solder for good measure.
 

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I got spark. I could see it with my naked eye in the light. Now I just need to button everything up and address a few other things to make sure I Don't fry the stator again.
 
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