Charging system wiring help


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Ive been working on a 1980 Cb750f Super Sport. I recently purchased a new reg/rec and hit a road block wiring. The new reg recs wiring harness seems to have a jumper wire come from one of the field coils to the ground.

As far as I'm aware the field coil doesn't have polarity. The factory diagram and the reg/rec diagram both don't show a field coil wire going to ground. Is there something thats states what goes where? It sure seems like if there is a ground, a certain coil should be wired to it.


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Where did you buy the Reg/Rec From ?

I just Recently replaced the whole charging system with parts from ricks motorsport Electric Except the Rotor Because they didn't have any new or rebuilt one on hand. Bought the new one from Parts Giant.

The parts I ordered were Identical to the OEM parts.

My bike had all the original hardware from 1980.

As far as i'm away The Reg/Rec Grounds out at the starter when The battery is fully charges and the battery ground when its charging.(I may be mistaken)

Also the Stator Rotor or field coil Is usually the culprit in these bikes charging system. Due to age and heat. According to my research and experience.

If I were to assume what your new reg/rec is doing is ground adding a path for the field coil to ground to assist if the field coil is grounding out on itself. I would replace the field coil if the reg/rec doesn't solve the issues your having.

Long story short The reg/rec shouldnt be jumping to ground like that on this bike in particular.
Looking at the product page I would assume that the reason for the jumper is because this reg/rec is suited for lithium ion. Which means it it needs to ground elsewhere before the battery when fully charged. I believe LI batteries don't like to act as a passthrough from ground as they can expand and explode when they are used like this.