New rectifier upgrade help

Slyman

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So my battery is not charging whatsoever. Was just messing arund with the old school voltage regulator and was about to adjust the points but I noticed my new one came

https://www.mikesxs.net/yamaha-xs650-xscharge-pma-rectifier-voltage-regulator-replacement.html

But now I'm guessing I can't just plug this in and it'll work right? I noticed it does have the same plug as the old reg/rec as the new one for the 3 yellow wires. But then there's a black plug with a red and green cover.

Orrr can I just plug these in?

Was able to find some info but people are talking about brown wires which this one doesn't have

Edit: well I realized the connector coming from the bike is female and the connector coming from the new reg/rec is female so can't do that today anyway but yea...



Edit: so now I realized the reg/rec I bought is for the pma kit. Will it work without it? Guessing not. My original alternator/stator and all that seems fine
 
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I used one of these three phase rectifiers off ebay, around $3-$4. My regulator was ok so I used that, but I think you could adapt adapt a regulator from any number of older vehicles. I did buy a combined reg/rect, but it didn't work too well, battery wasn't receiving sufficient charge.
 

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So my battery is not charging whatsoever.

You need to check and test the rotor before thinking about your Regulator and/or your rectifier. .............make sure your battery is fully charged and in top condition

This link is from Jim, who rewinds your original rotors. Jim has posted information regarding "Charging for Dummies", (post #2), and Post 3 is a trouble shooting guide for testing your rotor.
https://www.xs650.com/threads/rewound-alternator-rotor.54276/
 
I own a '79 Special and sometime around 15 or so years ago I went to a wrecker and bought a regulator from a '78 Matador (I think an International scout had the same one) for 5 bucks. He was glad to get rid of it. Works like a charm. For the rectifier I bought two bridge rectifiers from radio shack and bonded them to an old Pentium heat sink with thermal paste. I think all of this came from this forum somewhere. There seems to be a few more ways to skin a cat since I had to do it. I'll follow along for interest's sake. Cheers.
 
So I ended up finding that my battery was bad. Had the new battery for 3 days, took it out for a ride today and stalled a few blocks from my place, checked the battery with a multimeter, 10 volts. Almost got stuck but made it back home.

This charging system is driving me nuts, I just want it to work, I don't have the money to do all the major upgrades. And I'm kind of lost on these cheaper ones. Electric systems are not my forte. I was able to get it charger before I got the new battery but not sure if I had the correct spacing on the points

Got new brushes as well btw
 
Let's start clean here....
What year bike?
What size battery?
Original regulator?
Can you start it right now?
If you can, give us these numbers:

1. Batt voltage with the bike shut down and the key off=
2. Key on engine off=
3. Engine at idle=
4. Revved to about 3000rpm=

Some closeup pics of the battery installation, regulator installation and alternator.

The more info you give us, the better the odds we can get it working again.
 
Hmmm....well, I sure can't offer better than thread links posted above, but I'll try to answer specific questions on where you're stuck. Got a multi-meter, battery charger and a charged battery?

Jim's here: better than me
 
Let's start clean here....
What year bike?
What size battery?
Original regulator?
Can you start it right now?
If you can, give us these numbers:

1. Batt voltage with the bike shut down and the key off=
2. Key on engine off=
3. Engine at idle=
4. Revved to about 3000rpm=

Some closeup pics of the battery installation, regulator installation and alternator.

The more info you give us, the better the odds we can get it working again.

Ok finally had a chance to mess with is charged the battery overnight

1. 12.24v
2. 11.83v and going down
3. 11.83 and holding
4. No change

I should add that when I had the old battery, I had the points for the voltage regulator adjusted so that it was touching the top contact here when the bike was off (guessing this is actually right but I have to bend the thing so it's touching the top but the gap at the bottom is .014in). I could tell the battery was actively charging when the idle was low. When the charge was high enough and the contacts repelled, the idle would shoot up to 3000rpms.

Since the other day I adjusted the voltage regulator to be touching neither point with the bike off, didn't want to fry this new battery


Appreciate the help btw
 

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I could tell the battery was actively charging when the idle was low. When the charge was high enough and the contacts repelled, the idle would shoot up to 3000rpms.
Well it sounds like either the regulator is bad or you're not adjusting it correctly.
You might want to either try the adjustment again or upgrade to a modern regulator.
In the TECH section there's an article 5twins and I wrote on how to do the upgrade. It's inexpensive and easy to do. Without looking, I believer the second comment deals with your type of alternator.
 
For your regulator. Set the core then the gap. Then make your charge adjustment for 13.9 -14.3 (ish) when you briefly rev motor to 3000 or so rpm. One issue that @Jim, @5twins or @gggGary pointed out is that your ignition switch may have dirty contacts. That is an easy maintenence job to do and, like regulator adjustment, is well outlined in the tech section. Finally, if your regulator is unreliable a Napa Auto parts (AutoZone, O'Reilly s) solid state regulator is $15 or so online Ebay, Amazon etc. That does require you to make or piece together a mount and splice a few wires. Welcome and good luck. Pics, pics pics.
 
For your regulator. Set the core then the gap. Then make your charge adjustment for 13.9 -14.3 (ish) when you briefly rev motor to 3000 or so rpm.

Ah gotcha I was just adjusting it and considering what you just said I might not have done right.

How I have it now (.014in gap for the points with bike off (core gap might be off)) running and at idle (and revving it) it was attracted to the inner point, if I force it to touch the outer contact it charges the battery. So what I'm understanding is that when the charge reaches a certain point it repels (or the contact on the outside attracts? ) the points and charges the battery

Just kind of wondering what the function is of it touching the inner point? I saw a good video where it talked about it making it so the electricity doesn't flow backwards through the system but curious what the coil is for then.

Aside from that, doesn't the solid rectifier require some other upgrades? If that's already answered in thread well disregard this
Edit: just read that thread, might go that route if I can't get it figured out this way but just one question, is the rectifier upgrade required if I change the regulator? Guessing not. Other than that, I read that before and it makes way more sense now that I've been learning about this old vr


Again appreciate the help
 
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Ah gotcha I was just adjusting it and considering what you just said I might not have done right.

How I have it now (.014in gap for the points with bike off (core gap might be off)) running and at idle (and revving it) it was attracted to the inner point, if I force it to touch the outer contact it charges the battery. So what I'm understanding is that when the charge reaches a certain point it repels (or the contact on the outside attracts? ) the points and charges the battery

Just kind of wondering what the function is of it touching the inner point? I saw a good video where it talked about it making it so the electricity doesn't flow backwards through the system but curious what the coil is for then.

Aside from that, doesn't the solid rectifier require some other upgrades? If that's already answered in thread well disregard this
Edit: just read that thread, might go that route if I can't get it figured out this way but just one question, is the rectifier upgrade required if I change the regulator? Guessing not. Other than that, I read that before and it makes way more sense now that I've been learning about this old vr


Again appreciate the help
No. My OE rectifier works fine with a SS regulator.

It is best to have the regulator off the bike. Set core, set gap, reinstall. You mentioned "bend" something early on. Bend it back best you can to get your core and gap correct. Then you re install and can adjust the charge screw. Make sure you have made the @Jim, @5twins checks with regard to brushes, the resistance between slip rings, the brush voltage and the check of the magnetic field in the "charging for dummies" thread, tech section. I am a dummy but that section carried me through.
 
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Did bend it back as well as I could, and went back and checked it after i made that post, core gap is about .9mm so looks good. I will check that other thread out, thanks
 
Switched out the vr for the vr115, running great and charging properly!

I had some issues with it after I first got it in, no power at all, but didn't seem like that should be an issue. Took me an hour to realize I had a blown fuse 🙄

But yea thanks for the help everyone!
 
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