76C wiring question for the wizards...

GeorgeOC

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Hello everyone, thanks in advance for any support on this one...

Currently trying to button up the install of a replacement wiring harness from Mikes, into the 76' resto project. I have been following the diagrams from Clymer, and Jayel's that's in the tech section. There are few incongruities, possibly in the diagrams, possibly in the replacement harness. That has made things not super plug and play, but that wasn't expected...

Question I have has to do with the circuit involving the Red/white wire. There is a Red/White coming off each the starter solenoid, and the safety relay. There is a Red/white coming off my RH handlebar switch. The harness has a R/W for the headlight bucket, a 2-pin female near the colis, and a R/W at the back near the battery box.

I am confused because on the diagrams the orientation is different from where the parts sit on the machine itself. At the back of the harness is that one R/W off the harness, but there are two components back there with Red/White (relay and solenoid)...

If I connect everything into the circuit, is that correct? For example, using a 2-pin female terminal to connect the solenoid, and safety relay into the R/W coming off the back of the harness?
 

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Maxpete may chime in, he has done his recently...........In the meantime will these help.

76C Assembly manual - parts  Manualt19 19.jpg 76C Assembly manual - parts  Manualt27 27.jpg 76C Assembly manual - parts  Manualt28 28.jpg
From XSC Assembly manual............
 
dammit - where were these diagrams when I was wrestling with Lucille last winter/spring!!!! That headlight bucket schematic is excellent Skull!

Where'd you get that?
 
Pete, George, I'm sure i would have posted a link for you guys early in your post count on this forum. These come from thexscafe site in the manual section. look for the XS650C assembly manual.

Do Use with caution though...........There may be faults

I know posts can get lost when there are a lot of answers getting thrown about, but if links i post aren't read all i can say is i tried. Sorry guys.............
 
Not a prob Doug - it was a good learning experience. I had no idea there are so many different XS650 sites!
 
Your redwhite.jpg and redwhite2.jpg are both wrong. The engine stop switch only goes to the 2 coils. The Safety Relay only goes to the starter solnoid. There is no connection between those two.
The 1059 jpg wiring diagram is also wrong, for a couple of reasons. Its wrong because of what I just said about your two redwhite jpgs, and its wrong because it shows a red wire going from the 20 amp fuse to the Safety Relay.

On your 1059 wiring diagram, the red on the SR is supposed to be the power feed into the SR. Here's where it gets a little confusing.
Different years took the power feed for the SR from different locations. 1974,1977, and 1979 to 1983 years took the power feed from after the stop switch, i.e. a red white. My 1978 Special took the power feed for the SR from just after the ignition switch and before the stop switch i.e. a brown wire. The 1975/1976 wiring diagram in the TECH section has the power feed to the SR coming directly from the battery, which is wrong.
I suspect the 1975/1976 should be wired with the power feed to the SR coming from after the stop switch (red/white).

You can choose to wire the power feed to the SR either of the two ways above. I like the way my 78 Special is wired, because it allows me to turn on power with the ignition switch to test circuits on the bike, or crank the engine without having power to the ignition coils. That prevents accidently over heating the coils.
 
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@retiredgentleman Thank you for the detailed explanation.

Question: If the leads for the SR (safety relay) and the SS (starter solenoid) connect, that leaves an open Red/White from the harness in that area. There's connectivity from that wire to the R/W at the coil position. Would you happen to know where that rear facing R/W connects? If I understand your reply, the SR needs power... There are two RED leads back there. One presumably for the main fuse. The other to the SR???
 
I may be wrong, but isn't the one near the coil for the condenser? I found that the Miles harness fitted well, but there was a little confusion in the vicinity of the coils - at least partly because the colour of the wires was such that it was difficult to distinguish the brown from the black.
 
The condensers don't get a power wire. Each one connects to a points wire and filters the power running through it.
 
Hmmm. Makes sense on the condensers. At this point, I wonder if anyone has seen a correct/complete wiring diagram for the 1976 year?
 
@retiredgentleman Thank you for the detailed explanation.

Question: If the leads for the SR (safety relay) and the SS (starter solenoid) connect, that leaves an open Red/White from the harness in that area. There's connectivity from that wire to the R/W at the coil position. Would you happen to know where that rear facing R/W connects? If I understand your reply, the SR needs power... There are two RED leads back there. One presumably for the main fuse. The other to the SR???
That r/w you're talking about could be used to bring power from the coils position to the SR. That would be the power feed to the SR. That would make your bike wired similar to the 1974 ,1977 and 1979 to 1983 years, meaning there would only be power to the starter solnoid when the Stop switch (Kill sw) is in RUN.

2 red wires......................probably one red wire coming from the battery to the fuse, and the other red going from the fuse to the junction of the ignition switch and the rectifier output.
 
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The wiring diagram in post #12 has the same mistake that the 75/76 wiring diagram has in the TECH section of this site. It shows the battery/rectifier output connected directly to the SR. That is wrong because it means you could push the starter push button and crank the engine at any time, with no key even ON.
If you use the extra red/white (near the coils) and connect it to the same point as the 2 red/whites going to the coils, it would be the power feed to the SR. In other words you would have 3 red/whites connected together.

Wire it up and then do a few tests. Turn on the ignition switch and check for voltage (using a VOM) at the ignition coils red/white and at the starter solnoid red/white. There should be no voltage. Then put the Stop (Kill) switch in RUN, and you should see voltage at the coils red/white and at the starter solnoid red/white.

Don't leave power on (Kill sw in RUN) any longer than needed to do the quick test, so the coils don't heat up.
 
Is this the way i should be..................Br from ignition switch to stop switch and Y from stop switch could/should be R/W

d 75_76_XS650 B&C  Ignition circuit 1a.jpg
 
F**k the phones i still use a laptop..............Dogonit..........was referring to my Avatar quote and if you'd printed it, it would look like you'd be blaming me for you fuzzy pics...........gggggrrrrr ;)
 
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