Read jflugo's post above for a possible substitute from AutoZone as well. I can't reccomend it because I only reccomend parts that I have actually installed on my bike, but jflugo seemed to have good luck with it. Perhaps we could have an update from jflugo?
[21 Dec 2007 at 10:56 a.m.]
Still working well. Due to cold and wet weather, I haven't been able to ride as much as I'd like. But a couple of nights ago she felt very solid. Kick start was crisp (after a week of sitting), lights were consistently bright, and she was very responsive on the road. I also noticed that the previously erratic turn signal (erratic at higher RPM's, fine at idle & lower RPMs) now works fine. The battery has also kept a solid charge. All this is better than before the swap from the original OEM mechanical regulator.
I'm slowly building a new rectifier based on pamcopete's post to replace the 33-year old OEM - that's next on the agenda. After that it's the battery to coil relay connection and a new turn signal relay. I'll test after each and will continue reporting.
Additional comment on 2 January 2007 -- I completed the rectifier replacement, and she is just super now. Although it's still cold and wet, I'm riding her as much as I can -- just because she is a great bike now! I'll take another electrical measure in the next few weeks and will report back, but I'm very happy with my results. Best regards!
Post by laotzuistruth on Jan 9, 2008 16:36:03 GMT -5
just a quick update on the rectifier and regulator combo I put on. The rectifier seems to be working well and I ohm tested it and I did not burn out any of the diodes on the new rectifiers.
The regulator was a direct bolt on. I used the 727 unit as the above. I have a kind of crappy voltmeter, but at about 3k rpm, i am only reading about 12.8v or so.
I am assuming this is too low I will try to test the voltage with another voltmeter, once I ride it to my dads house. I put a battery tender on the bike whenever it is sitting, but other than a burnt rear running light, I have had no problems with anything else.
P.S. I am not running anything extra on the bike, just a brake light, halogen front light, and brake and turn signals when needed
P.S.S. If the charging does become a problem, I will likely move the voltage monitoring wire (brown wire) to the red wire on the battery per this thread
Well, it's important to wait a while, like maybe 3 minutes, after starting to allow the battery to "recover" from the effects of starting. You should also check "the usual suspects" especially the brushes if you are experiencing a low battery voltage. The voltage regulator and rectifier replacement can only work as well as the rest of the charging system is capable of.
Remove, measure the length and lightly sandpaper the brushes with a non coated very fine sandpaper. The coated sandpaper leaves a residue which can actually prevent proper contact between the brushes and the slip rings. While you have the brushes out, start the engine and use the eraser end of an ordinary pencil to clean the slip rings.
Last Edit: Jan 9, 2008 18:45:16 GMT -5 by pamcopete
Post by laotzuistruth on Jan 10, 2008 7:14:58 GMT -5
pamcopete, I appreciate the advice. The reason that I am betting that the stator, rotor, brushes and rest of the system is ok, is because before I changed the regulator and rectifier, I was registering about 17 to 18 volts at 3k rpm before the change.
Unless I blew something or shorted something within that short time frame, I am assuming (maybe incorrectly) that the rest of the system is in good shape.
Btw, as soon as I noted the 17 volts at 3k rpm, I stopped running the bike at all until I had the regulator/rectifier replaced.
I will feel it out and keep you posted, and I think the rear tail light blew when I had the 17 volt jump when I tested it before I changed the regulator/rectifier.
Checking in once again. You may recall, I used the Wells Manufacturing VR727 regulator, and built a new rectifier also based on Pamcopete's post. This weekend I also completed Pamcopete's Regulator Booster mod. I'm thrilled to say my results have been very positive so far. The Regulator Booster mod changes the electrical system so that battery voltage is regulated.
I measured voltage this morning after warming the bike up and going for a good 10-minute ride. The temperature outside was a sunny 25 degrees Farenheit. Measuring at the battery, the multimeter indicates around 14.12 (+/- .01) volts at idle, and a constant 14.17 volts at 3000+ RPM. I just checked the battery again tonight, and it shows 12.76 volts with the bike off.
The regulator's spec sheet says "The voltage reading @ 70 deg. F [sic] should be 13.8 to 14.8 volts", so I'm within spec.
I'm happy as a clam with my results, and would highly recommend these three mods.
What happend to the vr291? It's not listed anymore at partsamerica and four different stores here in Fargo, don't have this number to cross reference. Is it that the XS-650 Garage is such a force that we bought up everyone ever made? David.
I can't recommend either one because I don't recommend a part I haven't actually installed on my bike, but if you are successful, then please report back here for the benefit of the other members. These parts are warrantied, so if you have a problem, just return it, but be sure to keep the connector after you cut it off because some stores will not accept a return unless it is complete.
Also, check this post where another member had success with another equivalent part number (VR727):
Post by laotzuistruth on May 12, 2008 8:22:50 GMT -5
Well it looks like either the 727 unit undercharges, or i have the brown sensor wire at a spot in the circuit that it is not charging sufficiently.
I know it has been a while since i posted on this, but this is the first time the bike has been on about an 80 mile trek.
After being out this far, the battery just run out of juice With the headlight off, and the ability to kick start, it seemed to crank up and get home. The problem is is seems to charge ok, until it gets to the cruising rpm, and then it drops down a bit lower.
I am going to reroute that brown wire directly to the positive battery terminal as suggested and give it another go
I also have been looking for the VR291 regulator, no luck. I did call NAPA today, they have a VR1010 that is supposed to be a direct replacement for the 291. They are calling the warehouse to see if it has an orange or pink wire on the regulator. I will let you know what they find out and how it works. Has anyone ever installed this number regulator on a bike? Mine is a '77.
Well, looks can be deceiving. The regulator has to provide the proper current for the rotor resistance in both the minimum and maximum range of possible out put. Example is that the regulator has to work when the headlight is burned out at high RPM's or there is a danger that it will provide too high a voltage to the battery due to the reduced load.
The regulator also has to provide the correct polarity to the brush (positive) with the other brush grounded. The regulator for some automobiles and the '80 to '83 XS650's actually provides a pulsed ground.
I verified these possible conditions when I initially reccomended the VR291, including a full load and a reduced load (headlight off)voltage check for 14.5 Volts at the battery.
So, before you reccomend the VR169, you should conduct a series of tests and measurements, including the field resistance for the VW alternator.
I just took a quick look at the VR169 at Parts America and their price is $77.99.
Last Edit: Jun 3, 2008 13:14:24 GMT -5 by pamcopete
Thanks for the info Pete. The $77.00 sounds like a deal killer right there! The only reason i would even think of finding another one would be that the VR291 was last used in 1974 according to your application list so I'm worried that at some point it will become NLA.
I really appreciate all the work Pete and others have done on the aftermarket regulator but I couldn't source anything around here. I did have an idea of going with one of the used combo Shindengen units but felt I would be better off with something more up to date. In that regard, I connected with Oregon Motorcycle Parts and got one of Tony's solid state VR units www.oregonmotorcycleparts.com/vregulators.html For $48 I figure you can't go wrong and I wasn't disappointed. Plug and play all the way ;D If you can't get the $24.95 special this might be the solution for you.
Well, that may have already happened with the VR291, and I think in no small part due to it's popularity in this thread. However, they are certainly available at the wreckers, and I have posted a list of what vehicles used them, mostly AMC products from the '70's. Even if it has been sitting in a junk yard for 20 years, it's potted, so no deterioration should have occured.
Also, other members have found suitable new substitutes. Most recently from NAPA for about $25, so the beat goes on.
I'm sure out of the 5,000 + members who have viewed this thread that more than a few have gone ahead and sourced a replacement before their 30 year old mechanical regulator failed. If your crude mechanical regulator is still working when you replace it, then you can in good concience sell it on Ebay for.....$25?....., thats like getting a free solid state regulator with a one year warranty! I changed mine on my '78/E about 5 years ago. I still have the original, but I'm going to sell it on Ebay now that the price is up. I did the same thing on my '81/H.
There is only one thing surer than death and taxes......the regulator is going to fail some day.
Last Edit: Jun 3, 2008 16:23:07 GMT -5 by pamcopete
r80rt: :)This is a splendid write up, THANK YOU!!!!
Dec 26, 2015 16:54:05 GMT -5
mashermoto: What the what is this shoutbox for? Or should I shout, WHAT THE WHAT IS THIS SHOUTBOX FOR!
May 12, 2016 22:22:21 GMT -5
motormike: Good Day ...just a FYI.. Wild Cat is this Labor Day weekend. Still go'n on. A few 650's still make the scene. Various rides at different skill levels each day.. awards dinner sunday eve. BS in the park'n lot after dinner.
Aug 23, 2016 7:57:01 GMT -5
lsettle: First post in over 6 years!
Aug 28, 2016 19:45:17 GMT -5
kardon: Wow quiet here, where did they all go.
Oct 7, 2016 2:18:13 GMT -5
gggGary: XS650.com LOL
Feb 16, 2017 20:49:02 GMT -5
buell88: Anybody have any idea who built the xs650 tracker used in the Draggin Jeans Ad on Pipeburn?
May 16, 2017 16:24:09 GMT -5
joshua: The regulator/rectifier unit I got from Mikes PMA has closer hole spacing than original. Are we supposed to mill the holes to fit?
Jun 7, 2017 19:25:58 GMT -5
joshua: My bad. I found the bracket they supplied to mount the rectifier/regulator... Uh oh. How is this meant to work? Which way is it meant to mount? Looks like I have to use some spacers or something. Good instructions would be nice.
Jun 7, 2017 22:09:52 GMT -5
craig8johnson: Not sure if this is the right spot or not but oh well...
Jul 11, 2017 18:04:15 GMT -5
craig8johnson: I'm checking the charging system. I'm afraid I might have fried the last battery. With the solid state regulator (after market) what should it be charging at. The book says, I think, 15 volts. I'm hitting 17 when revved. Is that too high?
Jul 11, 2017 18:06:19 GMT -5
gggGary: Yes 17 volts is too high, about 14 volts is max, sounds like you don't have the right regulator or it's wired wrong.
Jul 13, 2017 6:54:33 GMT -5
dean: Just saying Hello, new member who is going to fix up a 79 XS650 that has seen its better days. I will definitely have lots of questions coming up.
Jun 23, 2018 16:45:32 GMT -5
tt650: Trying to breathe life into a 1980 that's been stored (indoors) for 25 yrs. Air filters are dry rotted. Have cleaned carbs but she only runs briefly on choke then stops. Need jet setting info and other ideas that might help her idle and rev.
Jul 3, 2018 19:15:19 GMT -5
trix13: Hey everyone! New to the forum and am fighting those gremlins!! New charging system, ignition switch, coil and fuse box. Resistance is higher than normal on the ignition pick up so I'm trying to find one. No such luck yet.
Aug 16, 2018 8:50:48 GMT -5
trix13: Also, even though all of my connections are clean, I cannot seem to find out why , when at higher rpms, I hit the signals and the rpms pulse with the signals...hahah. same with the brake light. I appreciate all input!!
Aug 16, 2018 8:55:08 GMT -5
bob99: how do I post a question. I am new to the forum
Jun 6, 2019 10:52:10 GMT -5
adlpc: Hello all! Been enjoying your edifying posts and discussions - and as a fan of the XS650 since my early teenage years happy that I now own a 1980 Special which I plan to turn into a vintage half faired racer. Thank you all for being here!
Oct 1, 2019 0:58:56 GMT -5
jimothyj: Hello everyone, I just joined & wish would have known about this site in 2014 when I brought my 1974 TX650A back from the grave. I have spent a good deal of $$ and alot of time on it. Just painted it and working on electrical, I will post pics soon,
Apr 10, 2021 2:14:13 GMT -5
louisvan: trix13 - I had a problem with my 1975 SX650. When I got to highway speeds, the engine lost power. The problem was in the connectors. At a certain vibration and the wind pushing on the wiring loom, the connector lost continuity. A bad crimp to the wire.
May 20, 2021 1:19:09 GMT -5