Author Topic: CB750F1 with M-unit charging system  (Read 652 times)

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Offline tomjoz

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CB750F1 with M-unit charging system
« on: February 23, 2020, 01:07:47 pm »
Hi Guys,
quick question, how can you test if the charging system is working as required? I just replaced the whole electric system with M-unit, new Ricks Reg/Rec new Li-Po battery all new wires etc. I connected everything and the electrics run well but I'm not sure if the battery is charging (I've checked the battery terminals with a voltmeter). Is that correct approach in that case? 

Cheers

Offline calj737

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Re: CB750F1 with M-unit charging system
« Reply #1 on: February 23, 2020, 02:04:07 pm »
The mUnit has nothing to do with the charging system. Key OFF, meter at battery terminals, what’s the voltage? Key ON, engine at idle, voltage at battery? Engine running, 4,000rpms, same test at terminals?
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Offline tomjoz

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Re: CB750F1 with M-unit charging system
« Reply #2 on: February 23, 2020, 03:02:15 pm »
The mUnit has nothing to do with the charging system. Key OFF, meter at battery terminals, what’s the voltage? Key ON, engine at idle, voltage at battery? Engine running, 4,000rpms, same test at terminals?

Will do and confirm :)
So I wired my new Req\Rec through MUnit so I thought this could have impact on the charging system?

Offline calj737

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Re: CB750F1 with M-unit charging system
« Reply #3 on: February 23, 2020, 03:32:43 pm »
How exactly did you do that?
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Offline tomjoz

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Re: CB750F1 with M-unit charging system
« Reply #4 on: February 23, 2020, 04:28:59 pm »
According to the attached diagrams from Revival:
1. Starter selenoid
2. General MUnit diagram
3. Rec/Req with Munit

Offline calj737

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Re: CB750F1 with M-unit charging system
« Reply #5 on: February 24, 2020, 03:39:12 am »
The BLACK wire from the RR is only a reference voltage for the Regulator side. As long as the output of the mUnit on that terminal equals the voltage read at the battery directly, you're fine. Proceed with the tests listed above.
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