Regulator question (I've done the homework but need a little help)

unitedhow

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I got my bike running well thanks to this site but the charing system is not working. I have read every thread on this site on this issue and they have been extremely helpful. Here's how the tests went.

Initial alternator test showed that the bike is not charging. I found that it had a parasitic draw. I cleaned the battery connections and the ground and the draw ceased (great!). Bike still not charging

Rectifier test showed that it is working properly.

Test on the three white wires coming from alternator are within spec. .79ohm

A feeler gauge hung magnetically from the case.

I attempted to test the voltage regulator but got nothing. (I'm not sure if this is because it is the solid state regulator and the test is different or not available)

Based on this information I assume that it is the regulator causing my issue. I have purchased r296 and pt173 from orielly's. I'm just not sure how to connect the wires. Can I use the original connector? Which wire connects to which?

This is a picture of the wiring on my bike
image.jpg
 
just did this today myself. this thread helped me out greatly. more over, the diagram on post #6 did more so than the conversation. I found that the black wire going to ground is not the only thing thats need to be grounded out. When placing my multimeter on the battery while running, the system did not charge the battery until i bolted the r-296 to the frame. I ran the black wire from the harness to the frame, AND bolted the r-296 to the frame and got volts at idle. For what its worth, it should not matter but the two frame ground points i used were seperate. Hope that helps

http://xs400.com/forum/showthread.php?t=12142
 
full


This is what I did. The black wire is attached to a bolt on the back of the holddown, and I pluged it in to the blackwire of the connector.


my album at
full
 
Arfstrom your pictures helped a ton

I did the same thing here's mine the connector added
image.jpg

I will run a ground from the back of the VR
I have also replaced the stock connection on the bike to accommodate the two plug connection (sorry if I'm using the wrong terms this is my first attempt at any electrical work) it is set up so that my blue wire on the VR connects to the brown wire on my bike. And green to green as per the diagram that maniac1886 shared.

I'm a little nervous to try it out
 
I suspect you will be fine. The original had a ground, since you only going with the two colors, try to mount the VR so that its touching metal, and you will have everything where everything just fine. I just didn't trust aluminum to be a good grounding pass thou metal. so with what I did there is no excuse. Good luck
 
Started it and... It was charging, but not much.

Rechecked the white wires and found the fraying :/
Looks like I will need to rewire that...

So if I'm reading correctly I need 14 gauge tinned wire is that correct? That is just for the three white wires right? What about the other two wires? How much of the wires do I need?

Thanks for all the help!
 
I had all sorts of problems with the 400s ive owend, I recently build a café style and was chasing tail with it un til I did some research and successfully adapted a pma charging system from the xs 650 it works great!! 14.5 volts at 2000 rpm. ill put up some pics of the modifications that were required to adapt the 650 pma
 
I would really like to see that

I did make some progress on my charging system. Now that I have replaced the voltage regulator with the r296 and replaced the PO's 30watt brake/tail lights with Oem 8watt bulbs and I replaced a broken front brake switch... Started it up and getting 12.8-13 at idle (maybe a little over) and 15.03 when revving. I've read that 15 is the max it should go is 15.03 ok? Could that just be variance from the multimeter I'm using?
 
Well being an XS650 fan, it didn't have a PMA. Not stock anyway. They started out using a Banshee rotor. A stator from a whole list of later bikes.
A few enterprising people started assembling kits of the parts. The supply of used parts has dwindled, they get new parts made to order for the kits.
So to say you used an XS650 PMA isn't exactly correct.
But I have read the threads on the PMA conversion on the XS400. There are advantages to a PMA. One, you can run without a battery. Any other advantages are in the imagination of others.
15 volts is actually a bit high. 14.5 is considered max. 14.1 or 14.2 is about right. Too high a voltage can be from several things.
The brown wire that goes to the regulator is a voltage sensing wire. Depending on where this brown wire is getting it's reference voltage it can throw off the output of your system. With the bike idling check the battery voltage, then check the voltage on the brown wire to the regulator. they should read the same.
If the brown wire voltage is lower than the battery voltage, it will cause the system to over charge. It could be dirty contacts in the key switch or a weak connection in the wiring some where.
A weak ground can cause the over charge. The brown wire supplies the voltage to be sensed but a poor ground can make the reading low.
Anytime the regulator senses a low voltage it charges more. Anything that causes a low voltage needs to be fixed.
Leo
 
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Good news!

Xsleo i did what you said and check the wires it was good so I remounted the VR on a piece of metal to the frame to ensure good grounding and sure enough it is charging in the 13's with the max I got 14.4 at 5k+

Finally :bike:

Thanks for all the help!

(Also everyone that said it would feel rewarding to accomplish this was right if you're having this problem stick with it... It's worth it)
 
So what your saying is for me knot to change a thing with my vr. Great ;)
Perhaps that ground wire I used, was a good idea.

Some times the pic does say a thousand words.
 
Your pictures were more than helpful I just didn't realize that the metal mounting to ground was so key. I had a ground wire (like yours) when I first installed it and thought that was enough but it wasn't until I mounted it on the metal bracket that I was getting the right volts
 
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