Bad Battery? Overcharging Issue? I sure Could use Some Help.

MplsMurr

1973 TX650
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Hello everyone, I had previously posted about getting a new charging system. Well, I fixed here up! My 1973 TX650 now has a functioning stock charging system with a solid state reg/rec unit. I had her fired up and charging! It was worth it. However, I am a bit confused. Maybe the community could provide some information for me:

I have a Shorai battery. Bought the charging system with the SS reg/rec unit. Wired it properly and checked to see if it was charging. The battery was between 13-13.5 volts at idle, jumped a bit to 14-14.2 volts at 3,000 rpm, I think I saw it read 15.2 volts at even higher rpms, and then it dropped back to 13-13.5 volts at idle.

So, I went for a bit of a ride, longer than I went before I had a good charging system. Stopped at a coffee shop for a quick cup, walked around my bike and heard a hissing sound. It was NOT the tire, but the battery. I unplugged the negative terminal. Had my coffee and went back to the bike an hour later. Plugged the negative back it. The battery read 13.5 volts. I turned the key on and none of the lights worked and battery read 0 volts. Turned it back off and battery read 12.7 volts.

I got picked up with my roadside assistants. Got home, and took a look. The battery was swollen on the sides. Very swollen. Very very swollen. I then disconnected the battery and put the old lead-acid to the bike, replaced the fuse and tested the charging again (stationary). Everything was back to normal.

I thought to ask the community before speaking with Shorai.

My questions:
Was this my fault or the battery?
Is my system overheating or overcharging?
Was the battery bad?
What do you think?
What should I do?
 
You lads have got to stop buying that poor quality, chinese made junk rec/reg unit, that Mikesxs and other after market sellers are selling to the public. Yes the rec/reg unit is over charging your battery, which is not surprisingly, very bad for batteries. No it is not the fault of the battery.

For your 1973 bike's stock alternator, buy yourself VR-115 nos automotive regulator. They work great on these bikes. Also replace your stock rectifier with a new 3 phase rectifier from E-bay. Much cheaper and much more reliable.

Edit;
I assume you followed the instruction sheet for the rec/ reg unit. If you did not connect a good ground connection to the case of the rec/reg, then it will default to charging at full voltage and voltage can go up to 17 volts or more.
 
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Yes, the VR115 is a wonderful thing. I recently found a substitute for it, the VR1010. This is the NAPA/Echlin equivalent for the VR115. I just scored one off eBay for $14 shipped to my door .....

FQ73vmk.jpg
 
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Thanks, guys! So, if I get the VR-115, can I wire it as such:

Simply cut the wires from the VR-115 and my stock reg. Then connect the wires as such...
Regulator....................... XS650 harness
orange & yellow.................brown (load side of ignition switch)
green...............................green (left outer brush)
black................................common black wire in harness or bare metal on frame.

*Mount this inside of my electronics box*
*The following link is AutoZones interchangable part*

Link:
http://www.ebay.com/itm/Voltage-Reg...ash=item3f4fc9585f:g:WoUAAOSw0QFXBwc3&vxp=mtr
____________________________________________

How would I wire the rectifier? Better way to attach it besides two nuts and two bolts and two-four washers?

http://www.ebay.com/itm/Amico-SQL-1...677055?hash=item4afe56bc3f:g:GhkAAOSwiYFXJ6kD

*Attach under the electronics box and it has the heatsink*
 
Yes, your wiring for the VR115 is correct. I don't cut the plugs off them. The wires are too short to reach the harness plug so I just make up an extension that will plug into the VR115 and then the harness. The length would vary depending on your mounting location and the harness plug location. Your '73 may mount the regulator and rectifier in different spots compared to my '78.

1jkIpTx.jpg


For the regulator end, I just use individual 1/4" spades, no plug .....

IT9g0fC.jpg


I combine the orange (or red) and yellow into one crimp on the harness end and use a connector plug that mates with the harness .....

MPhpUJQ.jpg


The rectifier wiring is pretty simple. There is a wiring diagram on the side of the unit. The 3 tabs in a row, the ones with the "squiggly" lines on the diagram, get the 3 white wires. It doesn't matter which white goes to what terminal. The "+" tab gets the red wire, the "-" tab gets the black one. I make up "L" shaped brackets to attach the rectifier to and then hang it off the bottom of the battery box. I also like to incorporate a tab on the bracket to hold the wires. Here's some I recently made up .....

C26qkLB.jpg


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THOpKcA.jpg


d0RyEPl.jpg
 
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Another nice little rectifier replacement can be had from an XS500, also found on some XS400s and 360s. It's a bit more modern version of the open air unit used on the 650s. It's totally enclosed and sealed in a little heat sink. The only "gotcha" is the plug is opposite of what you need. It has female connectors in it. You have to change them and the plug to the male type .....

IkRVXeK.jpg


gwHCW6m.jpg
 
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Don't get carried away on the size for the rectifier. You only need one that's rated at 25 amps.

5twins................real nice job using a mounting bracket for the rectifier cable.
 
One more thing to add - since I don't use a plug on the regulator end of my extension harness, I add a couple wire ties to hold the wires into the plug .....

7151KrL.jpg
 
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Thanks guys! Especially you 5twins! I will be purchasing these two if you agree that they will suffice. Also since the rectifier here has a heat sink, do I need another one? I will wire them up as you had recommended for my TX650.

P.S. Will it be a problem that the rectifier is rated for 100Amps with 1000 Volts?

P.S.S. The RECTIFIER needs to be exposed to air/wind so UNDER the seat/electronics box and the REGULATOR is okay INSIDE of the electronics box.

Regulator:
http://www.ebay.com/itm/Voltage-Reg...ash=item3f4fc9585f:g:WoUAAOSw0QFXBwc3&vxp=mtr

Rectifier:
http://www.ebay.com/itm/Amico-SQL-1...677055?hash=item4afe56bc3f:g:GhkAAOSwiYFXJ6kD
 
Since the rectifier has a heat sync, you won't need another, but as RG said, that 100 amp unit is way more capacity rating than you need. I don't think it will matter but maybe he will chime in here again and let you know for sure. That regulator should be fine but if you shop around on eBay some more, you might find one cheaper. I check from time to time and can eventually find them for $10 to $15.
 
As I already mentioned once in this thread, you only need a 25 amp rating for the rectifier. Will it be a problem to use a 100 amp rating.......................no its not a problem at all, if that is what you really want to do. I don't like to see lads installing electrical components that are way overrated for the job they are required to do. If you install a 100 amp unit and use it for a period on your bike, then you will come on the site and recommend the 100 amp size to other bikers. It starts an internet chain of false knowledge that feeds on itself.
 
Thanks, guys. I was only looking into the 100 amp since it was the one that fit all the criteria. However, I did not know for sure if it would cause any negative issues.
 
Update: I bought and installed the regulator and rectifier and have a brand new battery. I installed it as was described above, but I cannot get the advised readings. Mine measured at 12.9-13.1 volts at all RPMs from idle to 4,000. Any ideas as to what could be causing this to occur?
 
Update: I bought and installed the regulator and rectifier and have a brand new battery. I installed it as was described above, but I cannot get the advised readings. Mine measured at 12.9-13.1 volts at all RPMs from idle to 4,000. Any ideas as to what could be causing this to occur?

Your original problem of the rec/reg combo unit overcharging could have done damage to the rotor windings. You have to go back to basics......................i.e. you have to find out if the rotor has good windings to produce a good magnetic field. Remove both brushes and then measure ohms from one slip ring to the other slip ring. Use lowest scale and it should measure around 5 to 6 ohms. Also measure ohms from either slip ring to the rotor steel frame..................its should measure very high resistance.

Also, while the brushes are out, measure their length. They must be 3/8" or longer. I replace mine if they get down near 0.400". Clean the slip rings with some fine emery paper so that they are bright and shiney, which makes for low resistance.
 
Sorry for the delay, everyone. Still not working right. I was able to get some time and tinker with the bike this weekend. I removed the brushes and measured them. One was 1/2" long and the other was about 3/8" long. The rings were cleaned and measured out to read between 5 and 6 ohms. I then checked the readings on my stator and those were in the right range too. Double-checked my wiring from VR-115 and rectifier. Seem to be done right with strong connections. What am I missing here? This is driving me crazy. Should I buy new brushes?
 
Hi Murr,
of course you should, the brushes you have are WAY too short to work properly.
Note that I'm NOT saying that longer brushes will fix your problem, just that they won't be causing it.
 
Yes the 3/8" brush is too short. Buy and install new brushes.
12.9 to 13.1 volts @ 4000 rpm is definitely very poor..........................really no charging at all.
Once you have the new brushes installed, you should do some testing. Fully charge your battery with a bench charger, and install it into the bike. Measure the battery voltage. Connect your VOM leads to the 2 brush terminals, set to read voltage. Turn on the key and read the voltage across the 2 brushes. Engine is not running.

As an example, if you have 12.4 volts at the battery, with the key on, you should expect to see maybe 10.4 volts at the brushes. That indicates that normal current is flowing through the rotor, and you have a 2 volt drop from the battery to the brushes. That means the rotor will have a strong magnetic field.

Next, start and idle the engine, 1200 rpm. Measure battery voltage and measure across the 2 brushes again. Brushes should be around 10 to 11 volts (2 volts less than battery). Now rev the engine up to 3000+ rpm. The voltage across the 2 brushes should drop to 5.5 to 7 volts.
 
Thanks Fred and RG! I just ordered a new set of brushes and hope to install them right away since time has freed up for me now. RG, thanks for the detailed response. It will be very helpful, I appreciate it. Thanks, guys!
 
Update: I received my new brushes and new 35A rectifier earlier than expected. I installed them both, after I had cleaned the rotor rings with an eraser. Battery was fully charged at 13.3V. I turned the key on (engine not running) and tried to test the brushes, but they read 0V. I then tried measuring them WITH the engine running and still read 0V. I thought that was odd so decided to measure at the battery and see what numbers I get. I got 13.1/13.3 V at RPMs of 1,200-4,000. I inspected my wiring and everything checked out again. I am so confused and lost right now.
 
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