RR extra earth mod.

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VTR Phoenix
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RR extra earth mod.

Post by VTR Phoenix »

After my RR decided to crap itself I decided while it was apart to stick an extra earth going to the battery. The earth that sits behind the RR has two green wires one slightly thicker than the other. Does it matter which one I splice into to run an extra length to the battery negative terminal?
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tony.mon
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Re: RR extra earth mod.

Post by tony.mon »

Not sure about this, although I know it's a common mod.
Here's my thoughts on it...

Compare to the "normal" route:
The normal path for earth from the RR is via the frame (which is why you need to scrape back paint or powder coat firm under the RR) down to the motor mountings, and then back up the main earth bolted to the back of the engine to the battery. All of those links can carry hundreds of amps, assuming that you haven't overpainted or coated the frame to RR interface.

What you propose to do is to splice in to al already quite thin wire, via a joint, a section of thin wire which is meant to assist.

If the normal path fails, your bit of thin wire isn't going to be man enough to carry the load- think about why Honda used a thick and heavy earth wire to the battery in the first place*.

The RR is capable of putting out a lot of amps, so you would need a thick section of cable to connect it- bigger than the cross-sectional area of one of the yellow wires coming from the alternator, because due to overlapping phases there are more than one putting current in at all times.

But I'd rather make sure that all of the traditional route connections are good; if you do that then you don't need an alternative route.

Let's assume that the engine to frame bolts are tight, and so there's good continuity there.
The only places where you may get some resistance due to poor connection is either behind the RR or at one (or both) end of the main earth cable. Suggest you clean and ensure both of those ends are tight and secure, and get a good surface for the RR to clamp to.
And don't put the ring terminals BEHIND the RR- seen that done as well.

Do that and you shouldn't need a spare bit of wire spliced in at all.

Perhaps a better approach would be to use conductive paste behind the RR, like you would on a pc heatsink. Scuff the surfaces both sides with wet and dry, and over that surface area you have an excellent contact patch, which is also good for conducting heat, using the frame as a heatsink.

*yes, the main earth cable also needs to be man enough to carry the return path for 200 amp starter motor loads as well, which is why it's so heavy duty.
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VTR Phoenix
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Re: RR extra earth mod.

Post by VTR Phoenix »

I have a couple of spare cables that go from the engine to the negative terminal, the heavy duty ones. I was thinking of running it from the same bolt as the original earth ring connector straight to the battery.

Why shouldn't it go under the RR (that's where mine was mounted)
If it aint broke, get your bloody hands off it!
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popkat
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Re: RR extra earth mod.

Post by popkat »

On stock Firestorm reg/rec connector there is only 1 earth, 5 wires in total, 3 from the generator, a live and an earth, I just piggy back a wire about an inch from the block connector from the earth to the battery negative. the original earth is still in place.

When I've done it I've consistently seen voltage of around 14.8v, if you ride with the lights on this will lower a little, in any case it's not over 15v so ok.
I've done this mod not just on Storms, on a few other makes and models too. But I don't do it to everything, only something that I feel could benefit.

Also on Storms I've added a washer behind each of the reg/rec mounts to space the unit slightly further out to allow a little more air flow (I didn't do this on Robs bike)


My take on this mode is that it doesn't seem to hurt anything, maintains a good earth and doesn't effect any of the original wiring.. As for the rights and wrongs well I don't know :Shrug: There will always be differing opinions with valid points on either side, but it does seem to be effective.


* I must get round to doing it on my own bike, trouble is I only seem to pull the bike out occasionally to ride and it's never where my tools are.. I'm still on the original un finned reg/rec too, I do have a finned one just haven't been bothered to fit it.


.
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2014 CRMC Post classic Superbike champion.
2014 CRMC Post classic senior production champion. On a Suzuki Katana 1100
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tony.mon
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Re: RR extra earth mod.

Post by tony.mon »

popkat wrote:On stock Firestorm reg/rec connector there is only 1 earth, 5 wires in total, 3 from the generator, a live and an earth, I just piggy back a wire about an inch from the block connector from the earth to the battery negative. the original earth is still in place.

When I've done it I've consistently seen voltage of around 14.8v, if you ride with the lights on this will lower a little, in any case it's not over 15v so ok.
I've done this mod not just on Storms, on a few other makes and models too. But I don't do it to everything, only something that I feel could benefit.

Also on Storms I've added a washer behind each of the reg/rec mounts to space the unit slightly further out to allow a little more air flow (I didn't do this on Robs bike)


My take on this mode is that it doesn't seem to hurt anything, maintains a good earth and doesn't effect any of the original wiring.. As for the rights and wrongs well I don't know :Shrug: There will always be differing opinions with valid points on either side, but it does seem to be effective.


* I must get round to doing it on my own bike, trouble is I only seem to pull the bike out occasionally to ride and it's never where my tools are.. I'm still on the original un finned reg/rec too, I do have a finned one just haven't been bothered to fit it.


.
It certainly can't do any harm, I wonder why it would make any difference. Ring connectors under bolt head rather than under the RR? Because part of the function of the RR base is to conduct heat from the RR to the subframe. It takes a good contact to do that.

But, Malc, think of the extra weight of all that cable...... :p
It's not falling off, it's an upgrade opportunity.
VTR Phoenix
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Re: RR extra earth mod.

Post by VTR Phoenix »

I think I've got confused then, it the rr wire that I need to tap into and not the one with the ring piece
If it aint broke, get your bloody hands off it!
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popkat
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Re: RR extra earth mod.

Post by popkat »

VTR Phoenix wrote:I think I've got confused then, it the rr wire that I need to tap into and not the one with the ring piece

Correct, piggy back the earth off the loom by the block connector that plugs into the reg/rec

Any poor earth can kill a reg/rec, this will give a guarantee'd good earth and in theory your reg/rec shouldn't fail.


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http://www.bidefordmotorcycles.co.uk
2014 CRMC Post classic Superbike champion.
2014 CRMC Post classic senior production champion. On a Suzuki Katana 1100
My bikes, Firestorm, Suzuki GSX-s1000 Katana, VFR800Fi. Projects, 1986 popup Katana, 3 XJ600’s
VTR Phoenix
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Re: RR extra earth mod.

Post by VTR Phoenix »

That I believe is exactly what happened. The battery is turning her over good and strong so believe it was a bad earth as it just kept blowing the 30amp fuse. As soon as ignition was turn on about a second later a pop which was the fuse.

Thanks Malc, I'll sort that tomorrow ready for the replacement rr.
If it aint broke, get your bloody hands off it!
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macdee
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Re: RR extra earth mod.

Post by macdee »

Nice one men will have to get this done on the big girl
told you not to but oh no you knew better
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eezee29
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Re: RR extra earth mod.

Post by eezee29 »

cheers for the info
trying very hard to get over the 50 posts hurdle :lol:
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