Double check my wiring

kawabunga

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Wiring gurus, can you double check my wiring, please?

I have a '79 Standard model. Totally custom build with a fresh wire harness with all the safety switches and relays removed.
My question is in regards to the charging, starting and ignition systems. Nothing to do with lighting yet.
Stock rotor, points, electric start and coils. I did go for a combined regulator/rectifier from TC Bros.
I'm using an automotive style, 3-position key ignition with an OFF/ON/START position. (START is momentary).

The main thing that has me most confused right now is that all the diagrams I've found thus far have shown 3 white, 1 green, 1 brown, 1 blue and 1 yellow wire coming from the rotor. There is no brown coming from my rotor, it's black. I even pulled the sheathing back to see if I just had a discolored wire, it's not, it's definitely black.

Plus, all the diagrams I've found on the forums have some other combination than mine; be it the electric starter was removed, converted to a PMA or switched to electronic ignition. So, I just wanted to run my setup past someone else before I go ahead and hard wire it.

As of right now, I have a system that powers up, cranks over and has spark. I don't have carbs on it so I cannot actually verify running yet. But, I don't want to fry anything with the way I have it if it's not correct...

The reg/rec from TC Bros comes with plugs to go directly into the OEM harness, but I've ditched the entire thing so that doesn't work here. Although, I am using the OEM harness as a reference. The TC Bros reg/rec has two plugs. One 5-wire (3 white/1 red/1 black), one 2-wire (1 green/1 brown).

Here's my wiring so far:
3 white from rotor to 3 white on reg/rec
green from rotor to green on reg/rec
black from rotor to brown on reg/rec
yellow from rotor is open
yellow from rotor is open for neutral light yet
black on reg/rec to chassis ground
power to key comes from a 20A fused wire from battery positive
a wire from ON position of key to red reg/rec
a wire from ON position of key to power coils
START position of key runs to red/white wire of starter solenoid, blue/white wire goes to ground

Does this sound correct?

Here's my rudimentary attempt at making my own diagram.

EFerdxA.jpg


Thanks for checking!
 
No, not correct. your 79 uses the "B type" regulator.

3 white from rotor to 3 white on reg/rec. Correct.
green from rotor to green on reg/rec. Correct
black from rotor to brown on reg/rec. Not correct. Black on rotor is a ground... just like it is everywhere else. Brown to the reg/rec is switched power.
yellow from rotor is open. Not correct. That needs to go to a starter safety relay.
yellow from rotor is open for neutral light yet. Not correct. see above. Blue is neutral switch.
black on reg/rec to chassis ground. Correct.
power to key comes from a 20A fused wire from battery positive. Correct
a wire from ON position of key to red reg/rec. Not correct. Red from reg/rec needs to go direct to battery.
a wire from ON position of key to power coils. Needs to run through a kill switch
START position of key runs to red/white wire of starter solenoid, blue/white wire goes to ground. This too needs to run through the kill switch.

Untitledold.png
 
Also, as far as fuses go. Should I have any more or move the one I have?
Look at it this way... suppose your headlight power shorts out and blows the fuse. Now you're dead in the water 'cause there's no power to the coil. If you put a separate fuse in for each system (ignition in this case), a short somewhere else won't kill the whole bike.
 
Also, your new reg/rec... did you buy a type A or a type B? They won't interchange.
 
Thanks for the advice, Jim! I will dive into this more tonight.

I purchased this reg/rec from TC Bros:
http://www.tcbroschoppers.com/regulator-rectifier-yamaha-xs650-points-ignition-models.html

Also...
No safety relay switch, it's been removed. Like I said, nothing from the OEM harness is there anymore except for the charging, ignition and timing.
I meant blue instead of the second "yellow" in my original post. It's open for now because I'm not to that point in wiring. Just trying to get it running first.
I have no killswitch at this time. May add one eventually.

And good point on the fuses.
 
Also, so I’m sure what you’re saying.
Brown from reg/rec needs to go through the switch? Or it provides switch power?

Red on reg/rec goes direct to battery? That doesn’t put power to the reg/rec constantly? Not questioning the correctness, just trying to understand.

Where would the kill switch run in the START position of the key? Between the key and the solenoid?

Thanks.

black from rotor to brown on reg/rec. Not correct. Black on rotor is a ground... just like it is everywhere else. Brown to the reg/rec is switched power.

a wire from ON position of key to red reg/rec. Not correct. Red from reg/rec needs to go direct to the battery

START position of key runs to red/white wire of starter solenoid, blue/white wire goes to ground. This too needs to run through the kill switch.
View attachment 158558
 
Brown is switched power to the regulator. It needs it to sense battery voltage and to send it on to the rotor.
Red is the DC output of the rectifier. It goes direct to the battery to charge it. You could run it switched, but normally it's direct to the battery.
 
This is out of the Tech Section. It shows where to tie in the rec. output and everything fused.

wiring.png


Since you're using an automotive type ignition switch to run the starter, I'm not sure how it's wired internally. Got any diagrams on it?
 
Pretty basic switch. Got it from Lowbrow customs.
 

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So, looking at that diagram, the red wire from my reg/rec goes between the fuse going to the battery positive and the ignition switch. When I hook it up that way and put a test light to it, there’s current even with the key switched off. Is it supposed to be like that? Power going between the rec/reg and the battery when the bike is off.
 
No pic there. It just sez [ IMG ]
 
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When I hook it up that way and put a test light to it, there’s current even with the key switched off.
Did you mean voltage? Shouldn't be any current flow without the alternator charging.
Power going between the rec/reg and the battery when the bike is off.
Yes. The rec output to the batt is from the 6 diodes. Diodes are like one way check valves. They allow current to pass to the batt, but not allow current going the other way from the batt.
 
Did you mean voltage? Shouldn't be any current flow without the alternator charging.

Yes. The rec output to the batt is from the 6 diodes. Diodes are like one way check valves. They allow current to pass to the batt, but not allow current going the other way from the batt.

I’m not up on my terminology. I put my test light to a chassis ground and touched the red wire coming from the rec/reg and it lit up with the key off. I just want to make sure that’s all good.
 
I’m not up on my terminology. I put my test light to a chassis ground and touched the red wire coming from the rec/reg and it lit up with the key off. I just want to make sure that’s all good.
Yes, that's normal if you wired it as suggested. Here, I doctored your original diagram.

doctored.png
 
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