'79 special voltage regulator swap basic questions

I can tell see the thread number so I'm not 100% sure on which one you meant. I ended up buying 3 of the attached images for $12 in total, with shipping! (2 for spares). They appear to tick all the boxes for what is needed, that and a bit of heat sink and we will be golden. From what I read it looks right. Have I made an error?
 

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I can tell see the thread number so I'm not 100% sure on which one you meant. I ended up buying 3 of the attached images for $12 in total, with shipping! (2 for spares). They appear to tick all the boxes for what is needed, that and a bit of heat sink and we will be golden. From what I read it looks right. Have I made an error?
Those JayCar people don't know what they are talking about. Telling you to buy 3 was totally wrong. All you need is one of the items you have in the picture. You should be able to sell the other 2 to fellow riders.
I thought my post was clear on what you needed.
 
Im using my phone and it auto corrects when it shouldn't. What I meant was, it became clear on what was needed through your help and the thread. I intentionally got 3 as I would like spares, but if it works and all goes well I could pass them on to people in need here in Aus. Jaycar people are good at the basic but not the greatest for anything other than that.

Cheers for the help.
 
The section I didn't understand was the thread number 39, my phone doesn't show what number each post is. That's what I meant at the beginning.
 
There's no need to make a DIY Radio Shack rectifier any more. We've found 3 phase units with heat sinks for less than $10 .....

http://www.ebay.com/itm/25A-1000V-M...914?pt=LH_DefaultDomain_0&hash=item35da1188d2

All you need do is connect wires to it. A 25 amp unit is all that's needed so something in the 25 to 35 amp range will do just fine. 35s seem more plentiful.

5Twins,
That EBay seller of the recifier sold out. This appear to be an equivalent, am I correct?

http://www.ebay.com/itm/231523784365?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT
 
It may or may not make a difference but that single sale listing uses a track hanger not a through bolt.
 
Yes, and it also has an M6 hole threaded into the heat sink at the center. I didn't trust just that single center bolt so I added a couple smaller ones in the track .....

NewRec3.jpg
 
Got to love technology! Is there anything else we can replace with smaller parts tech wise? I build a electrics box and it stuffed tight, I would love to loose some outdated tech.
 
These new replacement rectifiers don't end up being much, if any, smaller than the originals once you add a heat sink but they are more modern, efficient, and much cheaper than motorcycle specific replacements. I consider the motorcycle specific units that some sellers charge $50 to $80 for to be a blatant rip-off. These $4 units that we use do exactly the same job for a fraction of the cost.

The new rectifier may give you a slight increase in charging output but for a real improvement, you should replace your antiquated mechanical regulator. This old stock unit works but it's output is very inconsistent, bouncing all over the place, up and down, regardless of RPMs. This works your rotor harder, making it jump through hoops to keep up with the constantly fluctuating voltage requests sent to it. A solid state automotive regulator works so much better and again, they can be had much cheaper than motorcycle specific units.
 
It's just crazy that people are charging those kinds of prices for basic electrical equipment. But then again, people always enjoy the plug and play, that plus the items don't have xs650 before the name, so they are never 100% sure if it will be right.

Speaking of, what type of regulator would be the best one to get? I imagine it will be some ubiquitous named thing that I could never guess haha
 
It's just crazy that people are charging those kinds of prices for basic electrical equipment. But then again, people always enjoy the plug and play, that plus the items don't have xs650 before the name, so they are never 100% sure if it will be right.

Speaking of, what type of regulator would be the best one to get? I imagine it will be some ubiquitous named thing that I could never guess haha
I use an automotive VR-115 on my 1978 Special. Its been giving me 14.2 volts for about 9 years now. It was designed to be a regulator on cars/trucks, which typically had 50 to 60 amp alternators, so its not working very hard to regulate my 16 amp alternator.
 
Yes, the VR-115 or it's equivalent is the usual choice for the '79 and older charging systems. You cannot use the regulator Bill linked to on your '78, it is the wrong kind. It is for the '80 and newer charging systems. When the TCI electronic ignition was added, the way the brushes were wired was changed. This was 1980 in the U.S. market, maybe a year or two later in some other markets. The earlier system on the points models grounded the inner brush full time through it's mounting screws and power was sent to the outer brush by the regulator. The regulator switched this power feed on and off to control or "regulate" the charging output. The later TCI equipped bikes were sort of opposite to this. The inner brush was fed constant switched power from the main harness and the outer brush was fed the ground by the regulator. This ground was switched on and off to control charging output. So, that means two different types of regulators were needed/used. The early system uses a power switching regulator. The later system uses a ground switching regulator.

The VR-115 is a power switching regulator and what you need for your '78. That VR794 that Bill linked to is a ground switching regulator and won't work on your '78.
 
Oh great!

Those VR-115's look great! On my '78 I have two regulators, would I need to buy two VR-115's, or would I just need one to replace both regulators?
 
I am at work at the moment and don't have any pictures. I have found one on google, I have one of these and then one that looks fairly identical. Im new to bikes and electronics, so it might not be a regulator.

XS2VoltageRegulator2.jpg
 
Yes, your picture is the stock regulator. What you think is another regulator is likely the Safety Relay (aka Headlight Relay).
Replace that original regulator with a VR-115, and your electrics will be very much happier.
To prevent confusion with parts, you need to get a manual such as a Haynes.
 
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