Charging system woes

[Trgglynn]

Hey all, first post. I bought a 1981 XS 650 knowing it has a charging issue. I have been lurking around here and the internet and trying to troubleshoot and familiarize myself with the system a bit. The issue I have is I am not getting voltage back to the battery, so at this point I have replaced the rotor and the stator with units from Mikes, and I am not getting magnetism nor output on the three white wires coming from the stator. The white wires off the stator ohm .5-.8 from each other, and the stator rotor ohms 5.6 between the rings.

I probably have a few electrical gremlins. The headlight doesn’t come on unless I jump two wires on the right side of the bike. I believe the safety relays are the issue there. Also, my bulbs are good but my neutral light isn’t coming on. Currently I have the connector for the neutral safety switch wired to a bolt to the frame. I’m kind of lost where to go with this. Is the regulator bad? Jumping the green wire on the pigtail leading to the rectifier to frame or ground does nothing.

Any ideas as to why I am not getting output from the stator?

 

[jetmechmarty]

I have replaced the rotor and the stator with units from Mikes,

That seldom goes well. I hope you still have the originals. Read your original rotor between the slip rings. It should indicate 5 ohms. The carbon brushes should exceed 7 mm in length.

 

[Its been a long time]

Can they be sent back for a refund? Then rewind the original?

 

[gggGary]

There's a thread (or forty) This one covers most of it;
https://www.xs650.com/threads/10561
Some pics from that thread

 

[Trgglynn]

That seldom goes well. I hope you still have the originals. Read your original rotor between the slip rings. It should indicate 5 ohms. The carbon brushes should exceed 7 mm in length.

So I have two original stator rotors from what I can tell. Do you know of a reputable person to rewind them? The new rotor I have reads 4.8 ohms after adjustment for the meter.

I replaced my ground strap today and after I did, I kept blowing the main fuse (20A). I traced it down to the stator unit, and it looks like when the brushes hit the new stator rotor from Mikes I would blow the main. From what I could tell all these rotors I have are not working and have friction wear on the two contacts off of the sides. I’m not knowledgeable enough to know if it’s relevant, but from what I can tell they seem to be the connections from the rings to the copper.

 

[Trgglynn]

There's a thread (or forty) This one covers most of it;
https://www.xs650.com/threads/10561
Some pics from that thread

Thank you so much!! I did not realize that the power is passed through the regulator prior to going to the brushes. Very helpful to know when diagnosing.

 

[Trgglynn]

Can they be sent back for a refund? Then rewind the original?

Do you have a guy for that?

 

[Kevin Kruse]

@Jim

https://www.xs650.com/threads/rewound-alternator-rotor.54276/

He rewound mine and many others here.

 

[Its been a long time]

Do you have a guy for that?

^^^^ See post #8.

 

[gggGary]

have friction wear on the two contacts off of the sides.

Lets see a pic of your stator/brushes installed?

 

[Trgglynn]

The little insulator tabs on the brushes I have flipped to the back side between the holder and the brush tabs. The stator is from Mikes.

 

[Trgglynn]

So I got a new stator rotor from Jim.
I’m still having issues with weak magnetism and low output. Any ideas on what I can troubleshoot or check outside of the stator, rotor and regulator?

 

[jetmechmarty]

Do you still have the original stator?

 

[Trgglynn]

Unfortunately I do not. I am getting magnetism, but it’s weak. A 0.008 feeler will magnetize to the nut holding the rotor on. I am thinking I have a wiring issue somewhere.

Side note, for some reason my neutral light is hot on both sides.

 

[jetmechmarty]

That tells me the first thing to check is the part number on the lamp. It’s probably for a license plate instead of an indicator.

 

[Trgglynn]

Well the thing is I can swap it out with the other two indicator bulbs and all three work per the blinker sockets.

Straying away from that, I am thinking I may have an issue in the harness. Being an 80s bike, I am wondering if I have a supply voltage problem. Assuming I have a short somewhere, would it be possible short would cause a weak magnetic field?

 

[jetmechmarty]

Well the thing is I can swap it out with the other two indicator bulbs and all three work per the blinker sockets.

Straying away from that, I am thinking I may have an issue in the harness. Being an 80s bike, I am wondering if I have a supply voltage problem. Assuming I have a short somewhere, would it be possible short would cause a weak magnetic field?

The weak field says you are not getting enough current through the rotor. That current has to flow through the brushes to charge the rotor. So make sure the brushes are making solid contact with the rotor. The voltage regulator controls that current.

Any connectors with corrosion can be causing you a problem.

 

[gggGary]

Well the thing is I can swap it out with the other two indicator bulbs and all three work per the blinker sockets.

Straying away from that, I am thinking I may have an issue in the harness. Being an 80s bike, I am wondering if I have a supply voltage problem. Assuming I have a short somewhere, would it be possible short would cause a weak magnetic field?

Picture of voltage regulator, fuse box, battery connections.
At some point a wise mechanic will switch from "looking for the problem" to verifying that everything is correct. Start at the battery check for a solid 12 volts under load and head down stream checking every connection and component as you go. It's late in the game for you but even now it's the FASTEST way to a reliable machine. We tend to get overwhelmed by how complex the wring seems but these are really pretty simple.
Fuse holders are a common issue on the specials.

Note the brushes are supplied by the main fuse and ignition switch so those and the wiring involved both +12 and grounds are your happy hunting ground. (see what I did there?) Wierdness on the neutral light would lead me to think (eliminate) a ground issue. Many the XS'r has been around the mulberry bush only to find the ground strap battery to frame and connections was a POS. I'll bet I've replaced 20 bad straps on various XS's through the SOIR. I wonder how many bikes ended up a the "back of the shed" cuz of a bad ground strap.
Filthy contacts inside the ignition switch another common issue.

 

[Scottike]

The neutral switch, (behind the left cylinder, on the top of the tranny), just makes a connection to ground to complete the neutral light circuit when the the bike is not in gear. That said, it may run through a relay to keep the engine from starting in gear. Hope this helps.

 

[Trgglynn]

The neutral switch, (behind the left cylinder, on the top of the tranny), just makes a connection to ground to complete the neutral light circuit when the the bike is not in gear. That said, it may run through a relay to keep the engine from starting in gear. Hope this helps.

gggGary, I need to investigate more based on your last post.

TL;DR Questions throughout, but some more critical ones at the bottom.

Thank you for the reply. That’s very useful because last I tested, I had 12volts on both light terminals. The bulb is original to when I bought the bike, it worked before and it still works in the blinker slot. So at some point I feel like the wiring mix up was self inflicted when I was in the headlight bucket. At least that’s my hypothesis (I installed a H4 halogen bulbed light with a new pigtail).

So today I tried to unplug and “rewire” connectors by putting in them in their proper sockets (hopefully). At one point my clutch was also engaging my starter… so now my clutch seems to allow me to kick start the bike by disabling the interlock, but still no neutral light, nor charging.

One thing that has really been throwing me off is the DC wiring. While I was in the bucket, I had been voltage testing and ohming wires to confirm that they are positive or negative. The wires change color so often and branch so many times it’s hard to understand it all. Also, new components changing color doesn’t help, so I try to verify by voltage or ohms. And I’m still really not sure where all the ground points are at.

So, I have been using this diagram for my wiring. I realized today that the diagram is for a 82(..?) because it has wiring, specifically relay wiring for the kickstand relay, which my bike doesn’t have.

I did notice on the teal colored line for the neutral that it branches to a diode today. That’s a big mystery to me.



Really right now my big questions are these:
1) would having crossed wires or a short somewhere stop the charging circuit from producing AC current.

2) Does the regulator supply the current to the stator? Can having a bad reg stop the stator from producing AC voltage? Even if it meters close to battery voltage at the rotor?

3) I get 10v through the yellow wire, does anyone know what might be missing to trip the headlight safety relay? Maybe I have something wired wrong elsewhere? I can open the relay manually by jumping the wires. The relay is OEM off of eBay. It came in some old packaging unopened but appears to be brand new from Yamaha.

4) Whatever the black hall sensor looking deal is at the 3 o’clock position on the stator, will the bike run without it working? Could it be worn out and causing me issues?

Sorry for such a long update. I appreciate all the replies and thank you. The whole point of the bike was to make it possible to further my education. I knew with my skill level in electrical it was going to be a headache, but it was a nightmare. I almost want to sell the bike at this point.