Expanded charging system guide (In progress)

peanut said:
follow the power.;)

Put the black lead (negative ) of your multimeter on bare metal anywhere on the frame .
Then turn ignition on and test that you have 12v+ at the outer brush of your rotor with the red positive meter lead .
( turn the ignition off for the following continuity test ) added for clarity
Then turn your multimeter to 'continuity' and with the black lead still on the chassis test with the red lead on the inner rotor ring that you have continuity .

The inner brush of your rotor should go straight to ground via the stator connector (black wire)
Click to expand...

Voltage at the outer brush with key on: 0
Continuity on the inner ring to chassis: no (open circuit)
 
OK, well we are making progress now. That combo rec/reg is now our prime suspect. You need to measure for voltage at a few places.
On the combo unit, lets check into the blue wire and the orange wire. Your instruction said to connect the brown wire from the key to the blue wire. Turn on the key and measure the voltage on the blue wire. That is the power feed to the rec/reg unit. If its got 12 volts, lets test some more. Now with the key on again, measure the voltage on the orange wire. You should have 11 or 12 volts on the orange wire, which is supposed to be connected to the green wire going to the left outer brush.
 
This particular reg/rec is from oregon motorcycle parts and is basically a separate reg and rec on a plate. Hand built. So the colors match the stock
Wiring.

Lemme see if I can figure out what the blue wire and the orange wire are.

Thanks for the help.
 
My mistake........................I read in one of your posts that you had the Mikesxs combo rec/reg, but now found the post where you said you went to the oregon cycle part. Disregard my blue and orange wire comments.
So you should have stock coloured wires. The voltage regulator part is quite simple, only 3 wires.
Unplug the voltage regulator from the bikes harness. Now with the VR plug in your hand, connect the black wire pin to battery negative. Connect the brown wire pin to battery positive. Measure the voltage on the green wire pin....................it should read around
11 to 11.5 volts, which means its good. If it measures 0 volts then the regulator is defective.
 
Last edited:
Well well well... I tracked down the culprit. A REALLY overcrushed crimp on the brown wire. I wasn't getting Voltage to the positive brush. I tested the wires for continuity and found the bullet connector wasn't passing current. Replaced it.

Voltage of 11.5 at the brush. Slap test passed with a strong field.

I won't know how the bike charges until I get the rear wheel back on the bike after a part shows up this week, but I'm feeling a LOT better about the prognosis. Fingers crossed. I guess it goes to show, don't skimp on cheap tools. Invest in a good crimper.

Thanks again for all the help, folks. If it wasn't for you all and this site, I'd be pushing a 400 lb roller.
 
Alright retiredgentleman, ready to help me now?! Lol. I have a 1980 xs650 it is 100% stock. This past summer I accidentally put jumper cables on the bike backwards and it blew a couple of the fuses. I replaced the fuses and I noticed it was not charging, sometimes it would charge and sometimes it would not, it was all over the place. My first thought was the regulator. So I replaced that. When I took it off, the connector was burnt. So I got new connectors and attempted to check for charging and now there is no charging at all. I checked the stator and that seemed fine, all of the white wires tested correctly. The rotor tested good as well. On the stator plug, one of the prongs for the white wire was burnt, and I replaced that plug. The brushes are new and I just have no clue what to do. I have checked everything that I can think of. I have been messing with it since august and am lost. I am a college student and cannot afford to take it to a shop. Any ideas??!!
 
do you have a voltmeter? If so while the bike is idling ground the
"top" brush rev it a bit also, what volts do you see? What regulator did you use as a replacement?
 
I bought the direct replacement from mikes, I have a multimeter, which brush is the top brush? The inner or outer?
 
You say you replaced some fuses. That does not mean they are in good condition. If the fuses are the original holders with glass fuses, you must replace the fuse panel with new automotive blade type fuse holders.
The surface of the slip rings on the rotor can get that dull oxidized look. You need to use some fine emery paper to clean up that surface so it is shiney, which will make for low resistance.
Next you want to check that you are getting +12 volts to the right (inner) brush, when you turn the key on..

If you get the +12 volts a the right inner brush, you then want to test for a strong magnetic field at the rotor (the slap test).
Unplug the rec/reg unit for the test. Have a jumper wire (16 gauge or larger) handy, with one end of it attached to a good bare metal ground or battery negative terminal. Suspend a metal object (wrench or other) about 3/4" from the rotor, turn on the key, and touch the jumper wire to the left outer brush terminal. The wrench should be pulled smartly over to the rotor.
 
You can't just replace the regulator on your model. It had a combo regulator/rectifier unit on it. If you just put a regulator on in it's place, now you're missing a component, the rectifier. The system won't work if that part is missing.
 
You will need to load test your red and brown wires in the harness also. though it's fairly rare, a reversed jumper cable is a wire/connection destroyer looking for a weak spot. Yamaha in it's infinite wisdom made several crimp connects IN the harness, roughly at the seat tank area. it's possible one of those burned off. Just one of the many areas that need to be tested. Don't forget basics like the ground strap, ground leads at frame, engine top mount etc.
Sorry but act in haste, repent at leisure applies....
 
It is already switched to the blade type Fuses. It passes the slap test, I am not sure if this is the Regulator Rectifier model or the regulator, I will try to order another one and will get back to you
 
Sito, if it passes the slap test, then your problem is almost certainly a defective regulator. A rectifier/regulator needs to have 6 or 7 wires (depends if it has a ground wire or if it uses the steel case as a ground) , while a regulator, by itself, only needs 3 wires.
Where did you buy the replacement rec/reg unit?
 
I wouldn't order the combo unit, or any unit for matter, from Mike's. They're very expensive and many report problems with them. Honestly, I think they're expensive junk. You can replace those components with a separate auto regulator and a 3 phase rectifier from the electronics industry. Cost will be less than $20.

http://www.ebay.com/itm/122128766123?_trksid=p2060778.m1438.l2649&ssPageName=STRK:MEBIDX:IT

http://www.ebay.com/itm/151314178350?_trksid=p2060778.m1438.l2649&ssPageName=STRK:MEBIDX:IT
 

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