Topic: m - unit wiring question

[macvit7906]

 
I'm about to start a full wire job and I have a few specific questions. I searched around and found a ton of helpful posts, and they answered pretty much all of my questions except for a few.

Attached is pretty much the wiring diagram I'll be using, made by revival cycles (convenient I didn't have to make a new one  ), it's pretty much my exact set up.
I'll be using a dynaS electronic ignition and coils
motogadget chronoclassic speedo
m-lock
Shorai LI battery and ricks reg/rec



1. what size main fuse should I be using? Like the diagram, my reg/rec will be connected to battery + via an integrated main fuse in the starter solenoid, however im not sure about the fuse size. Stock main fuse is 15A.

2. Am I correct in saying, the coils are grounded via the spark plugs? All they need is 12V switch power to them and to be connect to appropriate points? Arn't they grounded by the coil mounting bracket also?

3. the diagram mentions use of diodes for the turn signals ( labeled DIODE 1N4001) - anybody know where i can get these or have diode suggestions?

4. lastly, I'll be using an aftermarket clutch, so it has no clutch safety switch mounting spot. would it make more sense to wire the neutral switch inline with the starter solenoid so the bike can only start in neutral?

5. In addition to the diagram, I'll have to add a 1A fuse inline with power for the chronoclassic and M-lock, correct?

[Kyle2020]

Following...

[macvit7906]

Update to question 3:

Found the diodes: https://www.amazon.com/25-pcs-1N4001-Diode-50V/dp/B00I6IDGQI

[calj737]

1. & 5. The fuse requirements are in the motogadget documentation.
2. Correct
4. That works fine.

[macvit7906]

1. & 5. The fuse requirements are in the motogadget documentation.
2. Correct
4. That works fine.

Thanks Cal - still confused on #1

The motogadget m.unit booklet just says " a maximum of 40A fuse is needed between reg/reg and battery +.

I guess my question is, how do I choose how large of a main fuse I need?  for a CB750 and m.unit set up does the main fuse size that is needed change or should I stick with the stock 15A?

Thanks!

[calj737]

Based upon what little you have disclosed, I'd say 25a max.

[macvit7906]

Thanks! I'll go with a stock 15A for now

[macvit7906]

Based upon what little you have disclosed, I'd say 25a max.

Moving right along I want to verify the ricks reg/rec hook up.

So I'm assuming all 3 yellow connect to yellow and order doesn't matter, all the green on the reg/rec and engine harness side ground to the frame, the white on the engine harness is the positive field coil and goes to white on the reg/rec, and the red on the reg/rec goes to positive on battery. The green/red stripe is neutral switch and the blue red stripe is oil signal. Correct?

What about the black off the reg/rec? What does this do and where does that go to on the m.unit blue?

[calj737]

Correct.
Connect it to AUX. It’s the 12v reference for the Regulator.

[macvit7906]

Correct.
Connect it to AUX. It’s the 12v reference for the Regulator.

Thanks. AUX1 on the input or output side?

I've seen some folks connect it to "lock" on the input side in line with the key switch

[macvit7906]

Cal,

Thanks so much for the help so far. you're really helping move this along.

I'd also like to incorporate an "on-off" kill switch similar to OEM style, so I can still crank the engine but not power the ignition.
Is it as simple as disrupting the power to the ignition coils?

Just wire the kill switch between 12+ to the coils and 12+ from the battery, while not using the "kill" input on the m.unit?

[calj737]

The 12v reference can be on LOCK, but if you’re using m-Key, I don’t recommend it. I’d use AUX out.

For the coil power disruption, you can do as you described, but whatever switch you choose, make certain it’s rated for the current of the coils.

[macvit7906]

The 12v reference can be on LOCK, but if you’re using m-Key, I don’t recommend it. I’d use AUX out.

For the coil power disruption, you can do as you described, but whatever switch you choose, make certain it’s rated for the current of the coils.

The kill switch is rated at 6A, if I use a 6A inline fuse will that be sufficient for dynatek 5 ohm coils

[macvit7906]

The 12v reference can be on LOCK, but if you’re using m-Key, I don’t recommend it. I’d use AUX out.

For the coil power disruption, you can do as you described, but whatever switch you choose, make certain it’s rated for the current of the coils.

Figured out the switch. 6A dc should cover the ignition amperage.

Question about the 12V reference coming from the AUX1 out on the m unit blue. Would I have to configure the M unit blue to always be pushing power out of the AUX1-out in order for the 12V reference to work correctly?

I guess I dont understand what the 12V reference (black wire on reg/rec) is for.

[calj737]

Yes, if the Black wire is to provide any information to the Reg/Rec, then it must be connected to a "live" source.

The function is to inform the Regulator the status of the battery, whether it needs charging or not, how little or how much. If the voltage of the battery drops, the Black wire meters the Regulator to send more charging amps at the battery to maintain the draw. Without it, there would be no limit to the amps sent at the battery, up to 18v, then kaput or kaboom.

[macvit7906]

Yes, if the Black wire is to provide any information to the Reg/Rec, then it must be connected to a "live" source.

The function is to inform the Regulator the status of the battery, whether it needs charging or not, how little or how much. If the voltage of the battery drops, the Black wire meters the Regulator to send more charging amps at the battery to maintain the draw. Without it, there would be no limit to the amps sent at the battery, up to 18v, then kaput or kaboom.

good to know. I'll have to configure the m.unit so AUX is "on" with ignition on if it isnt by default already

[viken]

completely unrelated to m-unit but have y'all seen the NUUT Morty? Auto-reset fuses are all built in... https://nuut.ca/morty2x/