Author Topic: Simplified CB750 diagram  (Read 1502 times)

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Offline mysta2

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Simplified CB750 diagram
« on: September 30, 2014, 09:59:36 PM »
I just finished my diagram for my '75 and thought I would put it out there and get some feedback.



Uses: Pertronics ignition, a RR off a '91-'01 CB750, relays for the ignition and headlight (1wire into the headlight) and runs off a single 30A fuse built into a '94 VFR solenoid.

The single fuse is something I still question, but I'm not sure that I know how I want to split the circuits up.

KiefRichards

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Re: Simplified CB750 diagram
« Reply #1 on: September 30, 2014, 10:18:47 PM »
IMHO, I'd consider running 2 relays off directly off the battery, and use one for ignition, and the second relay just for the lighting. With the coils and all the lights/loads on one relay, you may have a significant voltage drop across it.
You could put a fuse before each relay, too.

Just 2 cents.

Offline mrbreeze

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Re: Simplified CB750 diagram
« Reply #2 on: September 30, 2014, 10:21:48 PM »
IMHO, I'd consider running 2 relays off directly off the battery, and use one for ignition, and the second relay just for the lighting. With the coils and all the lights/loads on one relay, you may have a significant voltage drop across it.
You could put a fuse before each relay, too.

Just 2 cents.
This would make troubleshooting a lot easier also.
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Offline evanphi

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Re: Simplified CB750 diagram
« Reply #3 on: October 01, 2014, 07:04:57 AM »
Agreed about the inline fuses...
--Evan

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She's a mix-matched (former) basket case, but she's mine.

CB750 Shop Manual (all years), searchable text PDF
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Offline lrutt

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Re: Simplified CB750 diagram
« Reply #4 on: October 01, 2014, 09:14:28 AM »
Definitely do a better job fusing things. Definitely main fuse coming off the batt then circuit fuse some of the others.

Also...the RR, what is the failure mode when it dies, short or open? I've seen some short and that is NOT good.
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Offline mysta2

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Re: Simplified CB750 diagram
« Reply #5 on: October 01, 2014, 11:26:24 AM »
More like this?



That solenoid would be the one from an R6 which has two fuses built into it.

(oops missed the switched power to the headlight relay. Use your imagination on that one)
« Last Edit: October 01, 2014, 12:21:39 PM by mysta2 »