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Discussion Starter #1
How do

After briefly running the '77 for the first time since rebuild, I've crashed into some electrical troubles. First up, the starter motor seems to be dead. Could've sworn I bench tested it when the engine was in bits, but I couldn't get any life out of it whatsoever. Solenoid clicked as it should, but that was it. Even (momentarily) wiring it directly to the battery produced nothing. Not sure what's going on there, but since I have the kickstart - which I kinda prefer - that's not too much of a problem.

The bigger issue was the total loss of power immediately after I tried the starter button. Previously, everything other than the starter worked. I've pretty much worked out where everything wires to and fixed the loose connectors. I've also had to overcome some grounding issues caused by the powdercoat on the frame. But everything else either lit up or honked, depending on what button I pressed.

Anyways, I got the bike to run by kicking it and thought that was about it. Then I tried the starter button. Nothing . . . and then everything crapped out and went dark. The battery's fine, as is the fuse. But I'm now in a situation where nothing functions regardless of the key position (other than off, obvs). So I'm on the lookout for obvious causes. I would also add nothing's burst into flames, so that's a plus.

Tested the continuity of most of the core cables and they seem fine. But in doing so, I've found that when the key is turned to the main 'on' positions, there's continuity between the point where the red power cable joins the distribution block within the headlight and the outer (metal) casing of the keyswitch. Since that casing bolts to/passes through the frame, I've got a horrible feeling that's not right. I can't find anything out there about it, so I really don't know but . . . doesn't the frame act as ground?

Anyone out there care to verify? And if something has gone wrong in the switch internals, are they repairable?

Thanks in advance.
 

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When all goes dead I start by removing, cleaning, and re-tightening the cable from battery to ground then the cable from battery to solenoid (starter relay). Then I use a test light (a multimeter also works) with the alligator clip on the battery ground terminal. Voltage at the battery positive? (they can just expire unexplicably) Voltage at starter relay? Fusebox? Ignition switch? etc etc etc
 

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Discussion Starter #3
Thanks JT.

Been trying all of that but nothing (so far) is showing up as being the smoking gun. Given that the starter seems to be dead, I've disconnected the starter solenoid wiring for now; the bike doesn't need it with the kicker and it's one less thing to get hung up on.

Essentially all the cables check out continuity-wise and so do most of the components. That's part of the reason I'm so confused. It's possible that the switch housing is s'posed to be live and that the powdercoat where the switch is mounted is not allowing it to make proper contact with the frame. It may have been sat just-so when the bike ran and then moved slightly out of place . . . which would mean the start button bit was just a coincidence.

Anyways, I used the distribution block to check out the keyswitch operation and from what I can tell, it operates fine internally when switching from off to on (no lights), on (lights) and parking light only - the various connections seem to be engaged/disengaged correctly. But since I can't see inside the switch, I'm hoping someone can confirm the last part of that puzzle so I can either eliminate it from enquiries or focus attention more closely on it.
 

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Discussion Starter #4
Answering my own question for future readers . . .

. . . yes, it looks like the keyswitch body should be live when the key is in the 'on' position.

After pulling things about a bit, I realised the battery was roached. Not obvious, because it would start out giving a decent reading, but connected up and with the ignition switch on, the power going to the coil was enough to drop the power very significantly. I was also getting confused by the fact the battery would recover a little after being off for ten minutes, but again the coil draw would kill it very fast.
 

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With the switch turned on there will be continuity between the power feed wire(red) and the grounded portion(the body) of the switch. Turning the switch on completes a circuit between the hot wire and ground, via the ignition and the neutral light. Slip a piece of paper between the points(to isolate the coil circuit) and put it in gear( to turn out the neutral light) and you won't see continuity with the switch on. Re-test your starter motor with a known good battery.
 
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