Diagnosing my charging system,

I've said it before, electrical is not my strong suit. I'm good at lifting heavy things and drinking beer Haha! I have been trying to educate myself this week. I have read everything I can possibly find on this forum and in my manual. So without further ado, here is where I'm at.
1. Bike doesn't charge
2. Failed slap test
3. No voltage at the hot brush when key is on
4. Battery is new and fully charged
5. Checked power both sides of the main fuse ( which is also new blade type fuse) all good, no drop in voltage.
6. Checked continuity of green power wire all the way from regulator to the hot brush. GOOD
7. Checked all the white stator wires with ohm meter , .5ohms, GOOD
8. Checked continuity of all white wires from rectifier plug all the way to stator. GOOD
9. Voltage regulator, performed all recommended tests from manual. All GOOD
10. Rotor , 5.5 ohms between rings, no short between rings and core. GOOD
11. Rectifier, FAIL FAIL FAIL all tests. I dissasembled it and looked for broken wires, didn't see any.
12. Performed visual inspection of all charging related wires and connections and they all look good.

Last night before I even started , I made the decision to upgrade my regulator and rectifier.
I ordered a new 3-phase bridge rectifier 30 amps, from EBay. It's on a slow boat from China ( literally) it could be a month before I have it. It was so cheap I should've ordered two, just in case the one I bought is bad.( Photo is just a sample not actual product)
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I also ordered a VR-115 voltage regulator, that will get here much sooner.
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By the way , I'm just curious, in the photo below, what is this green part on the voltage regulator? And why does it get hot when you turn the key on, without the bike running?
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So I'd love some input, did I miss anything?
Anything left that I need to check?
I sure hope this takes care of the charging problem. If not I've got the worlds prettiest boat anchor.
Thanks Bob
 
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Hmmmmm - it looks like you've nailed it down to the regulator or the rectifier - or both, Bob. I'm not an electrical wizard either, but I think that long thingy on the side of the regulator is a big resistor for dumping the extra current produced by the mighty 200 Watt alternator on your bike.

With all of the electrical grief I had on Lucille, I simply bought the combo unit (Part No. 24-2088) from MikesXS/XSDirect for about $60 CDN (I think that's around $7.25 US right now).
I know that many people will yell at me that I could have saved as much as $30 :yikes: if I had done the DIY - but I just didn't want to mess with it any longer....so here is what I bought and it works PERFECTLY. Frankly, you could likely go to an auto parts store and match one up for even less than the $59.95 CDN that XSDirect wanted.

Its 12 volts - and any automotive unit would be more than able to handle the roughly 17 ampere XS650 alternator current (200Watts/12 volts = 17 amps approx.).

24-2088.jpg


NOTE: unlike what is shown in their photo, XSDirect / MikesXS supplies the connectors come with the unit - but you have to mount them. It is not difficult at all - the key things to understand are:
  • the three yellow or white wires (the photo and the supplied instructions said yellow - but they were actually white on mine) - just connect them to the three identically coloured wires on your bike which will be in a (I think) 6-pin plug - they are all the same and there is no way to do it wrong because it is a 3-phase circuit;
  • you are supposed to ground the chassis (i.e. the body) of the reg-rec unit. All I did was drill an appropriately sized hole in one of the cooling fins and used a self-tapping screw to attach a little wire the other end of which I connected to a big bolt somewhere nearby on the frame (like an engine mounting bolt).
As I have said before, I mounted the unit directly under the battery box but it wouldn't fit right on the box. So I rigged up a large hose clamp around that triangular tube portion of the frame right behind the rear engine mount - and simply lashed it to the hose clamp with another self-tapper plus a couple of black zip-ties to the forward end. It has survived more than 1500 miles of Lucille's XS650C vibrations - and I think that the combination of a strong hose clamp with a bit of flexibility is protecting it from the shaking. From 3 feet away the thing is invisible - and being a modern component, it works.

Regulator-Rectifier_El-Cheapo-Mount.JPG


Regulator-Rectifier_Unit.JPG
 
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That green thing on the side of the voltage regulator relay is a high wattage resistor. Its actually 2 resistors, an 8 ohm and a 25 ohm. Its purpose is to provide a load for the alternator when the voltage goes higher than normal.
2 clues that tell us something:
You said no voltage at the hot brush, and the green resistor gets hot with just the key on. Those 2 things can only occur when the regulator thinks the voltage is very high i.e. 15 volts, but that is not possible, because you have only just turned the key on, so the voltage is likely around 12 to 12.5 volts.

This means the regulator relay contacts are incorrectly operated. It could be that the contacts have welded themselves closed or it could be a short circuit in the internal wiring of the regulator. Regardless, you have done the right thing by buying modern replacement parts. The VR-115 will work very well for you. The 30 amp 3 phase rectifier is a good choice also.
 
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Good - I was right about something electrical!!! My late Dad would pleased, proud (and he's be surprised as well....).

OK - so given what Ret'dGent has sussed out - have you looked at the contacts inside the voltage regulator? Perhaps you could gently separate them and clean the little point surfaces....and see if things work better (at least to get you going until the parts arrive).
Just a thought....

Pete
 
You're on the right path. GOOD choice of replacement regulator and rectifier too. You should be able to install those parts, test the voltage running at different RPM's, make a decision based on the outcome.

Scott
 
have you looked at the contacts inside the voltage regulator? Perhaps you could gently separate them and clean the little point surfaces....and see if things work better (at least to get you going until the parts arrive).
Just a thought....

Pete

Actually I removed it from the bike, opened it up, and cleaned the contact points with some very fine sandpaper and contact cleaner. Then ran all the recommended tests on the bench. Funny thing is it passed all the tests.
 
Dang! That is why I hate electrical stuff. Its like a woman:
  • you ask "What's wrong?"
  • she says - "Nothing, I'm fine..."
  • but you KNOW that something is wrong...
Dammit.

Now, when a connecting rod breaks - you know exactly what is wrong by just looking at it. No guess work needed.
 
Oops I edited my original post to reflect the correct amperage of the rectifier. It's 30 amps not 20.
Well I am replacing both, so hopefully that will take care of the problem.

RG, thanks for the input, it didn't seem right that it should heat up so, just from turning the key on.
 
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Oops I edited my original post to reflect the correct amperage of the rectifier. It's 30 amps not 20.
Well I am replacing both, so hopefully that will take care of the problem.

RG, thanks for the input, it didn't seem right that it should heat up so, just from turning the key on.
Good to hear it was a typo......................the 30 amp rectifier is a good choice.

You'll find that the VR-115 stays cool all the time. Using it in our motorcycles, it's not working hard at all, as it was designed to work with cars and trucks, that have 60 amp alternators, compared to our 16 amp alternators.

I don't know what testing you did on the OEM regulator, but it would be interesting to test it again, once you remove it to the bench.
If it was working correctly, your ohm meter should show almost zero resistance between the brown wire and the green wire.
 
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Were the two adjustments ever set on the regulator? Wonder if some PO didn't mess them up chasing a charging problem?
 
I don't know what testing you did on the OEM regulator, but it would be interesting to test it again, once you remove it to the bench.
If it was working correctly, your ohm meter should show almost zero resistance between the brown wire and the green wire.

I performed the following tests on the regulator, after removing it from the bike and sanding and cleanining the contact points. All tests performed on my workbench were straight out of the Clymer manual, with my Ohm meter.

1. Black wire to base of the unit....no reading.....GOOD
2. Black wire to brown wire....38 Ohms.....GOOD
3. Brown wire to green....no reading .....GOOD
4. Brown wire to green with contact midway between points....9.5 Ohms.....GOOD
5. Brown wire to green with contact moved to bottom point....8 Ohms....GOOD

So I don't know if I missed anything, but like I said, when it was installed on the bike, and I turned the key on, that green resister immediately got hot. Either way, the point is moot. My new regulator will be here within the week. Yay!

I think one of you electrical whizzes could have a nice little hobby/side business by making aftermarket regulators and rectifiers with all the wiring done and connectors that would just plug into the factory wiring harnesses. Btw, I was on Boats.net looking at the parts lists. The rectifiers are an obsolete part but when they were available they were $396.00!!!! :yikes:
 
"electrical whizzes" Somehow a full bladder and pasture fence is the only image that comes to mind. I do keep thinking I need to make an electrical mock up for bulging boxes of "probably good" charging components testing, maybe when I get the 1.5 HP variable speed pedestal buffer fired up.......... I'm close on the buffer project. Cuz I need it for a rear wheel hub clean up. cuz, cuz, cuz. LOL
 
Yes, without a functioning rectifier, it doesn't matter if the regulator works or not. The regulator just controls the output of the stator, the charging rate. The rectifier actually delivers it to your battery, after converting it from AC to DC.
 
Mailman.......................perhaps you and I are talking a different language at times.
Quote: "3. Brown wire to green....no reading .....GOOD"
To me that means an open circuit i.e. infinity resistance. Is that what you are saying?
 
Correct, no reading at all. An open circuit. If I'm misunderstanding something please let me know. Pretty much everything I know I learned in the last week.
 
Pic of the day. This is my second attempt to polish the right side case. The first time I put paint stripper on it for 4 hours and it didn't remove all the clear coat. I tried it again, here it is after an 18 hr soak with citrus stripper.
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And here it is after washing the stripper off and cleaning it with Blue Magic and finishing up with a clean buffing wheel mounted in a drill.
Never took the cover off. Never hit it with any buffing compound. I'll say it again, I love that Blue Magic.

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http://www.oregonmotorcycleparts.com/Reg_rec_units.html

VRREM7-XS for Yamaha 650 twins that originally came with a separate
regulator and rectifier

This unit requires a plugs into the original regulator and rectifier connectors on the wiring
harness but requires custom mounting. The leads are 10" long giving you plenty of options as to
where to mount it.

$145.00
VRREM7-YXS

Tony's biz gets high marks over at XS11.com
 
Yeah I went to their website and checked them out. It all looks like quality stuff he makes and I know there are a few guys here that swear by their products. I just wanted to take a swing at doing it myself and maybe learn a little something along the way.
 
Correct, no reading at all. An open circuit. If I'm misunderstanding something please let me know. Pretty much everything I know I learned in the last week.
Good..................we are talking the same language. Well , if the Clymer manual says that an open circuit is good, from green to brown, then the manual is wrong. With the regulator unplugged i.e. no energy to it, Green to Brown must be a short circuit or zero ohms resistance. Being open circuit is why you had no voltage to the rotor and no charging.
 
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