Earthing on reg/rec

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BrianC
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Earthing on reg/rec

Post by BrianC »

Getting ready to fit my mosfet reg/rec
Always wonderedif the base(the shiney metal bit) of the reg/rec should earth onto the subframe?

Thanks
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cheekykev
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Re: Earthing on reg/rec

Post by cheekykev »

Not sure on other peoples advise on this, I had my sub frame powder coated, I ran a tap down the original bolts holes to make sure the thread was clean, which would give me a good earth to the frame, then ran a separate earth wire from the bolt fixings directly to batteries earth terminal, my theory being, that if something goes wrong with the reg rec, I now have a direct earth, instead of relying on the frame, or the loom to earth.
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misnblu
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Re: Earthing on reg/rec

Post by misnblu »

cheekykev wrote: Mon Dec 14, 2020 11:38 am Not sure on other peoples advise on this, I had my sub frame powder coated, I ran a tap down the original bolts holes to make sure the thread was clean, which would give me a good earth to the frame, then ran a separate earth wire from the bolt fixings directly to batteries earth terminal, my theory being, that if something goes wrong with the reg rec, I now have a direct earth, instead of relying on the frame, or the loom to earth.
That's actually a good idea and something I'll be looking into on my recently installed Kawi MOSFET rec/reg.
Since I actually bolted the reg to the plate using nuts and bolts it's a simple job to add a ground from the battery directly to on of the bolts.

Now the only issue I've seen on these bikes is that with these batteries we're using the pos and neg battery connections aren't meant to add a bunch of additional wires to them at the battery.
:problem: :think:
So as the electronic tech I am I'd wanted to add some kind of barrier strip or multi-post grounding plate to the bike but there's no room anywhere to install something like this. :Wall: :Shrug:

I wanted to run a big three grounding system like I do on all my car builds and even wanted to upgrade the sizing of the ground wire from the neg post of the battery but space is at a premium as is the battery connection for bigger wire and connectors.

I've not given up hope just yet but it's a big change from car electrical systems to bikes and the limitations bikes have. :? :wink:
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tony.mon
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Re: Earthing on reg/rec

Post by tony.mon »

You can run an additional cable which is easier to route than one big fat one.
The only one where that's difficult to do is the main starter relay to motor cable, but all the others can be beefed up with a secondary cable in addition to the existing one.
It's not falling off, it's an upgrade opportunity.
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misnblu
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Re: Earthing on reg/rec

Post by misnblu »

tony.mon wrote: Tue Dec 15, 2020 11:04 pm You can run an additional cable which is easier to route than one big fat one.
The only one where that's difficult to do is the main starter relay to motor cable, but all the others can be beefed up with a secondary cable in addition to the existing one.
This is good logic for sure.
I'd propose a ground/ earth cable to the engine and chassis for better electrical grounding. :thumbup:

On the main starter relay to motor cable what makes it difficult to increase in size? :think:
6A950D89-BD11-4AFB-B90F-2307AED900E4.png
Is this the cable you're referring to?
With the exception of the small connections to the relay it still seems feasible to go up one cable size? :Shrug:

I wish I were home to get a bit deeper into the electrical end of this bike and have a better see of the possibilities. :lol: :biggrin
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tony.mon
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Re: Earthing on reg/rec

Post by tony.mon »

The starter cable is already big enough, but over time it increases resistance due to breaking down at the starter end, assuming that the starter motor bolt is ok.
So it doesn't need beefing up if in good condition, imho.

It's easy to check though.
If your engine turns over slowly then rig a secondary cable from 30 amp cooker cable, if it spins faster, theres your problem.

Without the secondary, you should be able to feel where on the cable it gets hottest when cranking.
It's not falling off, it's an upgrade opportunity.
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