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Replaced wiring harness, no starter

markst1

New member
Hello to all,
Just finished replacing wiring harness which burned up last month due to a short under the tank. (Thanks to all for helping me sort that out) Everything seems to work fine (all lights, horn, turn signals) except for the lack of starter motor. I have the schematic, and this particular (starter) circuit looks somewhat complicated what with the starer lock-out for not in neutral, override for clutch engagement.
Has anyone done a systematic trouble-shoot for lack of starter engagement? I guess I'll start at the switch, trace to the starter relay, then starter.
I am really excited to get this figured out and on the road again. While the bike was down for the wiring I did a bunch of other fixes including new tires, SJ top triple tree, new steering bearings. Got in much deeper than I had planned, but hopefully the work will all pay off.
Thanks
Theo Marks '74 R75/6
 
Nathan,
I am not sure which wires, post and tab you are referring to. The key switch seems to work fine (all lights, warning lights, ect are OK). Just nothing happens when the starter button on R handle bar is pushed.
Thanks,
Theo Marks
 
It's a /6, correct?

May be a silly question, but is the "re-start lockout switch" functioning and/or connected correctly? It's on the left perch, I believe.

Not really sure of what I'm talking about here; on my /5 no-restart circuit is built into the relay.
 
Nathan,
I am not sure which wires, post and tab you are referring to. The key switch seems to work fine (all lights, warning lights, ect are OK). Just nothing happens when the starter button on R handle bar is pushed.
Thanks,
Theo Marks

On the starter, there are 2 posts. A wire to the solenoid is on one, two wires from the wiring harness are on the other. A third, smaller wire from the harness is attached to a tab. I've troubleshooted (troubleshot?) with these wires, but I don't remember what combination yields what results. Just figured I'd make sure it's hooked up properly first.
 
I recently dealt with a similar issue and found out there are a few things that will cause the starter button to do nothing:

1. Bad or improperly wired clutch switch.

2. Bad or improperly wired diode (the one in the headlight shell, behind the contact board).

3. Bad starter switch

Also, make sure that the small push-on connector is making good contact to the tab on the starter. You may want to give it a small pinch with a pair of pliers to make sure it fits snuggly.
 
doh

Well, my fault (suprise). I checked back over everything carefully (including multiple photos that I took after the melt down). And low and behold, one of the wires from the started switch was connected to the wrong tab on the circuit board in the headlight shell. The wiring in the headlight shell a real hair-pie on the /6, hard to get to, hard to see.
All I can say is that I am glad that I took lots of pictures, really made trouble shooting this easier.
Bike is back on the road with everything working fine.
Thanks to all for the help.
Theo Marks '74 R75/6
 
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