Author Topic: CB550 m-unit wiring diagram  (Read 580 times)

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Offline Blakesblakey

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CB550 m-unit wiring diagram
« on: April 10, 2020, 09:18:30 pm »
Hello all! New user so sorry in advance if this has been asked a thousand times.  I recently got a 1974 cb550 project going, PO stripped all wiring down to just ignition so thought I may as well install a M-unit.  It does have electronic ignition so not quite sure how that goes into this, Looked through many diagrams on here that people had but couldn't find a complete one. Any help is apreciated!

Offline calj737

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Re: CB550 m-unit wiring diagram
« Reply #1 on: April 11, 2020, 05:23:11 am »
If you are trying to power the electronic ignition, run a wire from IGN, Aux 1 or 2 to it. The Lock port is for the “keyed” ignition to send power to the mUnit. Basically, just like you have it is fine.
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Offline bomorr

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Re: CB550 m-unit wiring diagram
« Reply #2 on: April 11, 2020, 05:27:29 am »
I always use revivals universal diagram and modify it for my builds. On this page they also have the AWG listed per slot which helps a lot as well.

https://technicalarticles.revivalcycles.com/hc/en-us/articles/360009106131-m-Unit-Blue-Basic-Universal-Wiring-Diagram

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Offline Blakesblakey

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Re: CB550 m-unit wiring diagram
« Reply #3 on: April 11, 2020, 06:03:25 am »
If you are trying to power the electronic ignition, run a wire from IGN, Aux 1 or 2 to it. The Lock port is for the “keyed” ignition to send power to the mUnit. Basically, just like you have it is fine.
   That makes sense, one thing that has me confused is this 12v switched feed that's showing on Rick's rectifier/regulator diagram.

I always use revivals universal diagram and modify it for my builds. On this page they also have the AWG listed per slot which helps a lot as well.

https://technicalarticles.revivalcycles.com/hc/en-us/articles/360009106131-m-Unit-Blue-Basic-Universal-Wiring-Diagram

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That AWG chart And diagram will help a lot.

Offline bomorr

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Re: CB550 m-unit wiring diagram
« Reply #4 on: April 11, 2020, 06:12:12 am »
Revivals diagrams have always helped me out. They also have a reg/rec diagram that dogs deeper into that wiring

https://technicalarticles.revivalcycles.com/hc/en-us/articles/360015253812-3-Phase-Field-Excited-Regulator-Rectifier

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Offline Blakesblakey

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Re: CB550 m-unit wiring diagram
« Reply #5 on: April 11, 2020, 06:24:37 am »
That helps out, I was trying to think of where to put that way to long.  Only thing I see is in the diagram it shows it on an Aux output, but the key on the right says to use ignition output. Does it matter which one? I'm not clear on what this wire does maybe that would help.   ;D

Offline Blakesblakey

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Re: CB550 m-unit wiring diagram
« Reply #6 on: April 11, 2020, 06:32:50 am »
Would the new wire from ignition out to rectifier be correct?

Offline bomorr

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Re: CB550 m-unit wiring diagram
« Reply #7 on: April 11, 2020, 06:39:56 am »
Would the new wire from ignition out to rectifier be correct?
That should work, if you don't plan on using the 2nd Aux port I would power the reg/reg through that for easy of wiring. The original munit v2 only had 1 Aux output that's why a lot of the diagrams you'll see have them with multiple lines going into that port.

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Offline Blakesblakey

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Re: CB550 m-unit wiring diagram
« Reply #8 on: April 11, 2020, 06:44:52 am »
Would the new wire from ignition out to rectifier be correct?
That should work, if you don't plan on using the 2nd Aux port I would power the reg/reg through that for easy of wiring. The original munit v2 only had 1 Aux output that's why a lot of the diagrams you'll see have them with multiple lines going into that port.

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Okay, if using the Aux 2 I would program it to be on with  ignition? Thanks.

Offline bomorr

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Re: CB550 m-unit wiring diagram
« Reply #9 on: April 11, 2020, 06:48:00 am »
Would the new wire from ignition out to rectifier be correct?
That should work, if you don't plan on using the 2nd Aux port I would power the reg/reg through that for easy of wiring. The original munit v2 only had 1 Aux output that's why a lot of the diagrams you'll see have them with multiple lines going into that port.

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Okay, if using the Aux 2 I would program it to be on with  ignition? Thanks.
Correct

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Offline MaxP

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Re: CB550 m-unit wiring diagram
« Reply #10 on: June 09, 2020, 02:48:38 am »
Hi Guys
I am wiring a 2 cylinder 450 CMX with a M..Unit (in attach my schematic)
Is there any sequence to connect the yellow cable form alternator to the rectifier ?
Cheers
Max
 

Offline calj737

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Re: CB550 m-unit wiring diagram
« Reply #11 on: June 09, 2020, 05:16:31 am »
Stator Yellow wires aren’t sequenced.
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Offline MaxP

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Re: CB550 m-unit wiring diagram
« Reply #12 on: June 09, 2020, 05:17:38 am »
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