I am helping a friend of my son rewire his 78 cb750k8 bike. Going to rip the old harness out and do a simple wiring job with new blade fuse box or in line holders. new vr-115 regulator and a 50 amp 3 phase rectifier. This is a points bike with separate regulator and rectifier
I come back here for help as I have tried the cb750 forum and not a lot of help there.
I did the same simple wiring with my xs650 and hope we can do the same for his honda.
Im not sure of the alternator on the honda if it is a field excited type or not. By schematics I think it might be. I see a green wire going down to what looks like a brush and then on to frame ground.
I see in the schematics a white wire going down to what I think is the other brush. It comes from the regulator. The alternator has 3 yellow a dark green (ground) I think a white wire. Not labeled.
My question is about the regulator of the vr-115 Having did this on my xs I tied the orange and yellow together and wired them to the 12v hot lug on my fuse block.
But I cant remember where I wired the black and green wire. I think the green went down to the brush but cant remember if it goes to the hot side or ground side.
If using the vr115 and the honda has a white wire sending needed 12v to the alternator then It seems I know I need to use the black and or green from the vr115 to the alternator but I just not sure which one would connect to that white wire.
In fact Im not sure if this 78 cb750 has brushes?: I did some searching and could not find brushes for this bike. It may be a pickup down there that the white and dark green wire go to.
I did some searching here and found a post where RG told how to use the vr115
orange & yellow.................brown (load side of ignition switch)
green...............................green (left outer brush)
black................................common black wire in harness or bare metal on frame.
So im thinking that the green from vr115 would go to the Honda white of the alternator and black go to frame ground.
If anyone can clue me in and help us on his project I would appreciate it greatly.
By the way all you fathers, I hope you have a good fathers day.
I come back here for help as I have tried the cb750 forum and not a lot of help there.
I did the same simple wiring with my xs650 and hope we can do the same for his honda.
Im not sure of the alternator on the honda if it is a field excited type or not. By schematics I think it might be. I see a green wire going down to what looks like a brush and then on to frame ground.
I see in the schematics a white wire going down to what I think is the other brush. It comes from the regulator. The alternator has 3 yellow a dark green (ground) I think a white wire. Not labeled.
My question is about the regulator of the vr-115 Having did this on my xs I tied the orange and yellow together and wired them to the 12v hot lug on my fuse block.
But I cant remember where I wired the black and green wire. I think the green went down to the brush but cant remember if it goes to the hot side or ground side.
If using the vr115 and the honda has a white wire sending needed 12v to the alternator then It seems I know I need to use the black and or green from the vr115 to the alternator but I just not sure which one would connect to that white wire.
In fact Im not sure if this 78 cb750 has brushes?: I did some searching and could not find brushes for this bike. It may be a pickup down there that the white and dark green wire go to.
I did some searching here and found a post where RG told how to use the vr115
orange & yellow.................brown (load side of ignition switch)
green...............................green (left outer brush)
black................................common black wire in harness or bare metal on frame.
So im thinking that the green from vr115 would go to the Honda white of the alternator and black go to frame ground.
If anyone can clue me in and help us on his project I would appreciate it greatly.
By the way all you fathers, I hope you have a good fathers day.
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