Electrical upgrade to M unit blue

johnalb

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I am fitting an m unit blue on my 750 project and have hit a snag! I would like to retain the oem switchs. Which requires some alteration to the way the switchs work, changing from switched live to switched earth.
Has anyone done this and if so could they post a diagram and description on how to do it please.
Thanks
 
I should imagine if you're handy with a soldering iron it should be possible to convert the switches to switched earth?

Loki
 
I should imagine if you're handy with a soldering iron it should be possible to convert the switches to switched earth?

Loki
Its the knowing what to do and how to do it that is the issue.
Where electrics are concerned I have limited knowledge, I have managed to get the vast majority of the more straight forward bits working, its the indicators and the OEM switch's I need advice on how to do that.
 
I can only add to this by saying... I was going down the same path until I attempted to open the right handle bar switch and resolder smaller wires. Attempting to remove one of the internal switches, I broke the plastic toggle which activates the switch. At this point, I gave up. If I had to buy new switches to replace those which no longer function that well,, why not just bite the bullet and end the misery. The push button switces work as intended with the m-unit. I did rewire my entire bike. But also I used the m-button in the handle bar which eliminated some wires. I also reused some existing wires to keep the oem color scheme as much as possible.

My project was an entire tear down. I purchased it last Oct. There was so much rust that I could not bare leaving it in that shape. I have replaced the old reg/rec and fuses. The stator and points remain at the moment. Nearly everything has been powdercoated.

If you still want to go the route of using oem switches, there is an excellent video by Classic Octane, click HERE. I have looked over YouTube several times and this is the best IMHO. Easy to follow, no nonsense,,,, and good luck.
 

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I can only add to this by saying... I was going down the same path until I attempted to open the right handle bar switch and re-solder smaller wires. Attempting to remove one of the internal switches, I broke the plastic toggle which activates the switch. At this point, I gave up. If I had to buy new switches to replace those which no longer function that well,, why not just bite the bullet and end the misery. The push button switches work as intended with the m-unit. I did rewire my entire bike. But also I used the m-button in the handle bar which eliminated some wires. I also reused some existing wires to keep the oem colour scheme as much as possible.

My project was an entire tear down. I purchased it last Oct. There was so much rust that I could not bare leaving it in that shape. I have replaced the old reg/rec and fuses. The stator and points remain at the moment. Nearly everything has been powder coated.

If you still want to go the route of using oem switches, there is an excellent video by Classic Octane, click HERE. I have looked over YouTube several times and this is the best IMHO. Easy to follow, no nonsense,,,, and good luck.
I have watched the classic octane video so many times I have lost count and much of what he explains is excellent and works! however some aspects of the wiring he skips over with limited explanation, one such aspect is the indicators, that is the one element I just cant seem to get right.
I have quite a few wiring diagrams posted by various builders who have installed M units, one thing stands out more than anything else! not one of them installs the M unit Blue the same way, so I am trying different aspects from various diagrams!!!!!
only time will tell I am not in a rush.
 
LightGreen/Red is Neutral
DarkBlue/Red is Oil
Black is Power for Neutral and Oil, which only receive a ground signal from the sensors

Blue is Right Turn
Orange is Left Turn
Green is Ground

High Beam, I think is White (should be the only wire left after resolving those above)
 
LightGreen/Red is Neutral
DarkBlue/Red is Oil
Black is Power for Neutral and Oil, which only receive a ground signal from the sensors

Blue is Right Turn
Orange is Left Turn
Green is Ground

High Beam, I think is White (should be the only wire left after resolving those above)
The only issue I have with wire colours is that repro switch's have more wires than is shown on my Kojak colour wiring diagram, I can only assume the Chinese makers of these repro switch's put additional colours for other Honda models to cover more options.
I have the vast majority of my wiring done, some of which is very simple, to retain the OEM switch's for Headlight and indicators is the most complicated part of wiring the M Unit Blue.
I do have an auto electrician on stand by to sort it but Im recovering from a major op so ive been trying to do as much as I can whilst out of commission.
 
If you do not have wiring diagrams for the repro switches, then your auto electrician is your best and easiest route. If it is frustrating for you and not enjoyment to concur, then give up and hire the help. I wish you the best of luck.
 
If you do not have wiring diagrams for the repro switches, then your auto electrician is your best and easiest route. If it is frustrating for you and not enjoyment to concur, then give up and hire the help. I wish you the best of luck.
Not at all frustrating, I just dont like not being able to work it out, Ive been rebuilding the bike since 2019 when Covid came along, Then Cancer for my wife and then Me Too so those are the things that make it frustrating because it stops me concentrating on the job at hand!!!!
I'm only 73 so hope to have enough time to get it done before I pop my clogs.
 
If you still want to work on it yourself, I would suggest to start very small. For instance, if all the wires from the right side switches go into the headligt bucket, identify two of the wires that are connected to the start button. Then you can ground one side and run the other side to the Start Input. Just take it one circuit at a time.
 
If you still want to work on it yourself, I would suggest to start very small. For instance, if all the wires from the right side switches go into the headligt bucket, identify two of the wires that are connected to the start button. Then you can ground one side and run the other side to the Start Input. Just take it one circuit at a time.
Thanks for your input, I have sorted the lights tonight and will turn my attention to the indicators next, I have had 1 side working in the past but have never managed to get both sides working???

Regards John
 
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