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Discussion Starter · #1 ·
This is asking about a 1975 CB750K

I just got my new electric ignition and dyna dual output 3 ohm coils.


As you can see in this first picture, there were no coils or spark plug wires when i bought the bike.

I am having trouble figuring out how to wire it. The dyna wire instructions and the Clymer manual assume you are replacing coils, not starting from scratch.

The second picture shows the wiring harness wires that need to be connected.

Do any of you know what each of the wires are? Can you tell me which wires to connect to the coils?

The wires in the second photo are, from left to right, Yellow, Blue, Black/White, Green, Black.

The Honda manual says to connect the yellow, blue, and Black White leads to the wiring harness. The dyna coils have 2 connection points on each coil.

Also, the second picture shows 5 wires and there are only 4 connection points??

Finally, someone told me not to forget to ground the coils. As you can see there is no mounting bracket with the bike. I will have something fabricated once I tear this bike down, but for now I need to temporarily mount them so I can make sure she runs. If I use hose clamps to mount the coils, do i just need to connect a wire from either side of the coil to the frame somewhere? Or do i need to ground both sides of the coil?





 

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Discussion Starter · #2 ·
Just after posting I went back to look at all the diagrams that I have.

I now think that the yellow goes to one coil, the blue to the other, and the white/black gets split with one lead going to each coil.

Is that right?

If so, how do I ground the coils?

What do the green and black wires go to?

Thanks,
Mut
 

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Discussion Starter · #4 ·
Here is the diagram. I had to take a picture of it and zoomed in on the coils part.

As far as where I am: I changed the oil. I have a new battery, dyna electric ignition, rectifier, and am putting it together so I can start it and see how it runs. I am taking ( i think) your advise and getting it working 1st then tearing it down to do the cosmetics.

The electric ignition is supplied with its own harness. I think it is designed to plug into the original harness, which it does.

Do you have a take on how to ground the core? I am assuming that if you connect the coils to the bike with the stock mounting hardware you would also be grounding it. Since I plan to use hose clamps i will need to ground the core. I think I know what this means, we'll see.

We'll see if it runs.

 
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