Voltage Regulator

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kuthe64

XS650 Enthusiast
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I have an 81 xs650 and in the fall it was being difficult and the headlight would not always turn on. After it completely died on the highway I took it to my mechanic and he said that it was the voltage regulator. I've looked at most of threads on here about replacing the rec/voltage reg, but those post are from 2010 and the parts numbers they used are not coming up on advance auto or napa. Just wondering if anyone could help me out with exactly what parts i need. From what i got from reading the threads was that i do not need the nylon screws since it is a model later than 1980, is this correct? Any help/diagrams would be very helpful i have done mechanical work before but this will be my first electrical.
 
I did the Radio shack/Chrysler mod to my '80SG. Works great!. I too, took the numbers from the original Pete writeup to NAPA and they didn't cross over to anything. I asked for a regulator to a 70's Chrysler and got a Chrome one that looked the same as in the write up. Under $20 as I recall. Went to Radio Shack and got the rectifiers. Mounted the Regulater where the old TCI was mounted which was under the battery cage. The rectifers were mounted on a peice of aluminum mounted where the factory Rectifer/Regultor was. No nylon screws needed. Wire it up right and it works great.
BTW. I believe the write up was in XS650 Garage.com
 
I figured out which regulator it is (the top one)

but does anyone know which rectifier to get? I just keep reading everyone calling it the radio shack rectifier.

any help would be great, thanks
 
No, he doesn't want the VR-115, he wants that 1st one in his link, because his bike is an '80 or newer and has the brushes wired differently. He will want to build the same rectifier like we did though.
 
5twins said:
No, he doesn't want the VR-115, he wants that 1st one in his link, because his bike is an '80 or newer and has the brushes wired differently. He will want to build the same rectifier like we did though.
Click to expand...

Ooops! I stand corrected!! Thanks, 5twins!
 
Yes, you are wrong. You're not building the rectifier part, you buy that already made. What you have to build is a mount plate for it and add wires to it, that's all. Read that thread YL linked to, all the info you need is there. I prefer the 3 phase unit from eBay, that way you only need one. The single phase units from Radio Shack require that you buy and use two.

http://www.ebay.com/itm/35-AMP-3-TH...d=100011&prg=1005&rk=2&rkt=5&sd=400182097335&

..... and if you want to get fancy, here's one built right into a heat sink already. It has a higher rating than we need but I think it should work fine. Someone correct me if I'm wrong .....

http://www.ebay.com/itm/80-AMP-RECT...d=100005&prg=1088&rk=1&rkt=5&sd=261313978134&
 
Before you start replacing stuff, I might suggest to figure out if it's actually the regulator.
Your mechanic said it was, how did he decide that? Did he just check to see if it was charging? Did he check the ohms on the slip rings? Ohm the stator? Did he check the brushes?
Have you read through the charging trouble shooting guide?
Leo
 
5twins said:
Yes, you are wrong. You're not building the rectifier part, you buy that already made. What you have to build is a mount plate for it and add wires to it, that's all. Read that thread YL linked to, all the info you need is there. I prefer the 3 phase unit from eBay, that way you only need one. The single phase units from Radio Shack require that you buy and use two.

http://www.ebay.com/itm/35-AMP-3-TH...d=100011&prg=1005&rk=2&rkt=5&sd=400182097335&

..... and if you want to get fancy, here's one built right into a heat sink already. It has a higher rating than we need but I think it should work fine. Someone correct me if I'm wrong .....

http://www.ebay.com/itm/80-AMP-RECT...d=100005&prg=1088&rk=1&rkt=5&sd=261313978134&
Click to expand...

Yes the 80 amp would work just fine, but it would be overkill for sure. Also the large terminals/ fit to wire sizes, etc. might not work well.

The 35 amp unit is more than adequite.
 
Yes, it's a good idea to replace the ancient regulators and rectifiers on these bikes, but they may not even be the cause of your problem.
 
As both XSLeo and 5twins have said, you should not assume the regulator is bad.

With these bikes you want to start with the basic areas first. Failure of the headlight to come on when the engine starts, may be due to the Safety Relay not operating due to low voltage from the alternator. Low voltage from the alternator could be as simple as the brushes are to short, or a failed rotor is also very common.

Learn to use your VOM for voltage and resistance measurements. Here is a good link to read:
http://www.xs650.com/forum/showthread.php?t=10561
 

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