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Discussion Starter · #1 ·
So I'm loving my new LED headlight. Based on some of the reviews, I wasn't sure I'd notice a difference in visibility but I definitely do. However, my charging voltage has increased since I installed it. Is that because it uses less power? Before installing the LED, my afterrmarket voltmeter (which is tapped into the headlight lead), would never read more than 14 volts. Now it's often above 15. One time, after starting the bike after it had sat for over a week, it went to 16.5 (but only for a minute or two).

Everything seems to be fine and has been for the past few weeks since installing the LED, but is this something I should be concerned about? Is it going to harm my R/R or stator, etc.?
 

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I think that 16.5 is way too high. I have LED bulbs for basically everything except the gauges and never see above 14.5. Do you have another voltmeter to compare against? If you do take a reading right at the battery and see what you voltage is at a few different RPM ranges, (idle, 3K etc) a faulty R/R can cause the voltage to go high. After market meters can be finicky so it’s best to check with an external if you can.
 

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Discussion Starter · #3 ·
Ok, so here are my findings:
I connected an external voltmeter to the battery directly. Readings were pretty much the same as my wired meter; usually about half a volt higher. While running the bike, RPMs made no discernible difference in the readings. However, there were a few distinct "clicks" that would occur every so often where the voltage would go from nominal battery voltage (around 13v) to 15+ (as high as 17 today!). The lights would get brighter when that happened too. But then, sometimes after a minute or so, there would be another so-called 'click' and the lights and voltage would drop to normal again. By 'click', I'm not referring to an audible click, but a visible difference in the voltage and lighting. It's possible there was an audible click too but it would be hard to tell with the bike running.

Installing the LED headlight must have been coincidental to this voltage behavior, because I swapped in the halogen again, plugged the relay back in with no effect.

I had just put in an AGM a short while before the LED but that wouldn't make any difference either, would it?

Moving along, I then unplugged the wires from the R/R to conduct the resistance tests, as outlined in Clymer. The first picture is from the manual, showing the various readings from terminal to terminal. The second picture shows my results in the same format.

I confess that I am not very savvy doing resistance tests. What I mean by that is that I don't have much idea what I'm doing. I know the probes need to be clean and tight and that the meter needs to be set to measure resistance. My new digital meter automatically changes scale depending on the readings, so that's supposed to be easier I guess but is also more confusing, at least to me.

I am hoping some of you can help me interpret these readings. None of them are what the book calls for but at least a few seem pretty close. One thing that definitely stands out though is that the "M" terminal consistently does Nothing (hence the "N" in the table). It never registers anything no matter what I do. What does that terminal do and what does it mean when it's dead?How about the other readings?

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Here’s the pic from my manual. It’s showing the same readings with the pin out above I’m assuming you have that info as well. I do not understand what the “N’s” are on your chart. Do you have the ability to lock the ohmmeter on a specific range like 10, 100, or 1K ohms? The auto switching is cool but can be confusing if you’re not sure what you’re looking at. I’d rather be more thorough before telling you that your R/R is bad. Those voltage levels and the lights changing brightness do not sound right at all though.


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Discussion Starter · #5 ·
Yes, that's the correct pinout diagram (I should have included that in my post, sorry). The "N" stands for Nothing. That's what happened when I tested each terminal when combined with the M terminal. I didn't know what else to put to describe that result.
Unfortunately, I do not have the ability to lock my meter on any particular scale.
Thanks for bearing with me.
 

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When you say the meter does nothing, what’s on the display? Does it say 1.000 or something like that? Or maybe you could post pic or clip of it.
 

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Discussion Starter · #7 ·
When you say the meter does nothing, what’s on the display? Does it say 1.000 or something like that?
The meter set for resistance starts out as 0.L. That's what it says on the digital readout. If you tap the probes together, it will read 0000. You can set it to beeb for that too. When I say it does nothing, I mean that it stays right on the same reading as it starts at, which is 0.L. Does that help? I could send you a pic but that's all it would show: 0.L.
(I'll be away at work for a while)
 

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Your Ns all coincide with the infinity symbols on the chart in the manual, except a couple places that are supposed to be infinity, you have a certain number of ohms resistance.

Two of those readings are from the B-G and the B-A123.

I think your RR is defective or on its way out, both by the readings and the high voltage. Anything 16v or higher means the regulator isn't limiting the voltage.

The switching you're seeing is probably the circuitry in the RR failing and then coming back.

It's probably close to blowing light bulbs, I've had that happen with old mechanical voltage regulators, blew every bulb on the vehicle.

The M terminal on the stock system is the Monitor, it reads battery voltage back to the RR. And if I'm not mistaken, your N matches infinity. The MOSFET RR wiring does away with the M terminal/wire.

With the RR connected I would expect to see battery voltage on the M wire.

Thinking your RR is going out in a bad way, hope you don't blow any bulbs.
 

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Discussion Starter · #9 ·
Ok, thanks guys. Not great news but gives me an excuse to look into a MOFSET - one of the recommended mods. I'll need to read up on the threads as to the procedure for switching over. I assume the battery box has to come out - or is it easier to take the exhaust all apart and go at it from underneath?
 

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Ok, thanks guys. Not great news but gives me an excuse to look into a MOFSET - one of the recommended mods. I'll need to read up on the threads as to the procedure for switching over. I assume the battery box has to come out - or is it easier to take the exhaust all apart and go at it from underneath?
I left mine in place and mounted the new one under the left side cover. The MOSFET I have is too large for the stock location anyway.

Ominous Darkness brought up the idea of removing the battery box with the RR attached, but I don't think he's had time to try that yet.
 

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Finally got around to checking the downloaded manual about RR removal.

There's two ways, remove some bolts and items, turn the battery box on it's side on the bike, remove the RR.

Or, remove all the above items, remove the starter solenoid, slide the battery box completely out on the right side.

Check manual for specifics, some pics there too.

So no contortionist act needed, and hopefully no drilling of screws.
 

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I left the original regulator in place on my son's bike but pulled it on mine. Both bikes have the Mosfet mounted on the left side next to the sude cover. Mine is pretty much hidden by my saddlebag. I removed my regulator by just using ratcheting box end wrenches after soaking the bolts with PB Blaster from inside the battery box.

It does not have to be removed if you don't want to. However if all the hoses, charcoal cannister and stock regulator are removed there is a lot of room under there and it looks cleaner.
 
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I had the same thing going on, with the "clicks" of sudden voltage change. It was a failing RR. I too mounted the new one elsewhere while leaving the old one in place. Figured it was a back up if the new one failed completely (ie to get home rather than stranded). Check your stator wiring visually while you're at it. Mine was corroded and about a year after the new RR was installed, I started having low voltage issues.

FYI, "O.L." is how some meters display values beyond their measuring range. It stands for OverLoad. Overload sounds potentially damaging, but for resistance it's totally safe. If you see this while measuring volts or amps, it can be dangerous to you or the meter. Though I have a meter that will sometimes flash O.L. when the battery is low and it's still searching for the proper voltage range.

Some auto ranging meters have a "range" button to lock in the range, but some are only auto ranging.
 

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Discussion Starter · #15 ·
I've spent the bulk of the morning researching this whole MOFSET thing. From what I understand, the benefits are stable charging voltage and cooler operation. The recommended connection method also results in larger gauge wires to the battery. I still have a couple of questions though in light of all that:

Namely, is it really worth $140 more than buying a regular R/R for $20 on eBay? Obviously those of you who've done the mod think so, but why? Is it for stator insurance? On a similar note, will the MOFSET cause the stator wires to run cooler too? Mine have been pretty toasty, but is that because my R/R has been on its way out?

Another question: My R/R harness was already removed by the PO. The wires each have their own female spade connector. None of the pictures for the MOFSETs show the terminals on the unit itself. Can I just plug my female spades of the three stator wires directly to the unit rather than cutting them again to use the supplied harness? I could make my own battery cables too for that matter as I have some heavy gauge wire and a maxifuse kicking around somewhere. Then I could buy just naked MOFSET.

Do any of you have pics of relocated R/Rs inside the side cover? I'm curious how that's done. Would it be totally ghetto and/or foolhardy to just use industrial velcro to attach it to the fuse box cover in there?
 

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Discussion Starter · #16 ·
Incidentally, I just noticed something else, as shown in the following picture. It's those three yellow wires on the left. Unless I'm mistaken, those are the three wires coming from the stator. But rather than going straight to the R/R, which is literally right there, why did Kawasaki add another few feet of wire to run them up with the other wires, then across the top of the frame and then down the other side of the JB? Do they go into or through something else important on the way?

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While I'm already running the risk of being miserly, I figure I might as well ask this also:

What about using a R/R from an '86 Shadow 500 in place of mine, relocated of course? The wiring looks similar, except it uses double wires for the red and green (or brown in the case of the VN). I'm merely asking because I just so happen to have one of those on hand. It would cost me nothing and I'd be up and running in minutes. But of course, I really do want to postpone any stator failure as long as possible too so if the prevailing wisdom is to wait and spend more $ for MOFSET, that's what I'll do.
 

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Honestly I believe in “buy nice, or buy twice”, the $20 version of either a shunt type(stock) r/r or a MOSFET r/r is most likely a knockoff or very low quality item. I haven’t done this upgrade yet but plan too hopefully over the summer. I’ve been through the stator failure and I want to make sure I can make the electrical system on this bike as reliable as I can.

Here’s a couple links of what I’m looking at



 

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Discussion Starter · #18 ·
Thanks for the reply. I've placed my order!:) I'd still be curious to hear or see how folks have done the relocation mounting.
 

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There’s some pics further down in this thread

 

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Thanks for the reply. I've placed my order!:) I'd still be curious to hear or see how folks have done the relocation mounting.
I've got a pic, will put it up. I made a cardboard pattern and transferred it to a piece of flat aluminum from an old frying pan . Easy to cut, easy to bend.

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I sat down with a sheet of card stock and a pair of scissors, cut the card to the width of the RR, then trimmed it to fit in the frame over the top two battery box bolts.

Then I folded the card in two places so it came out and down, leaving a gap between the JB and the card, while also allowing a gap between the RR and side cover once installed.

Lay the pattern flat over the metal and transfer the fold lines, cut lines, and bolt holes to the metal.

I carry a 10mm T-handle in case I need to see the fuse box, but never needed it.

Industrial Velcro would probably work fine if you can get enough area to stick it to the bike frame or battery box/JB. Someone here attached theirs to the back of the side cover.

Nice thing about the connectors, they're more weatherproof than bare spades.

Nice thing about the MOSFET rewiring, it takes the charging circuit out of the JB, while eliminating the stock RR wiring and connectors. Adding the Blue Wire mod , and cutting the stator wire feed to the JB, removes the 50v AC from the JB.

Here's the most simple MOSFET wiring diagram I know of...

 
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