Regulator/rectifier combo for stock charging system?

A -'79 or '80- ? There are slight differences.
 
Neither, the charging system is....a '71 I think but I may have used the '77 I have. I am not trying to use a stock harness. I am OK with doing the nylon screw mod. Looking to keep it as simple as possible.
 
-'79 means pre 1979. '80- means post 1980. It's all in the hyphen placement. Lol. As long as the circuit is the same you'll be OK.
 
In my opinion, all the motorcycle specific combo units are a giant waste of money, a rip-off. You can assemble your our separate units using an automotive regulator and a rectifier from the electronics world for as little as $20.
 
Do search on Rec-Reg and should have many options. From Electro-Mechanical stock (-79) to total electronic (80-) or aftermarket total electronic like the Radio Shack/ Chrysler (like I run) or variations there of. Off the self 3 phase rectifiers and Fiat reg.
 
In regards to the generic rectifiers, there has been some discussion, as you will find in the suggested threads, of the super-cheap ones from China going bad.
I would be careful in getting one, and perhaps select an item that has been solidly recommended by members.
I put one together from Radio Shack rectifiers 5 years ago, and its performing fine. Then I installed this one
p.jpg

Brand New SQLF30A Bridge Rectifier 3-Phase Diode 30A 1200V
( 400714167691 )

($3.65 from dealbestshop in China) in my '75, and it makes me a bit nervous, altho it is functioning well at the moment. It might be one of those "super-cheap" and fragile items.
 
In regards to the generic rectifiers, there has been some discussion, as you will find in the suggested threads, of the super-cheap ones from China going bad.
I would be careful in getting one, and perhaps select an item that has been solidly recommended by members.
I put one together from Radio Shack rectifiers 5 years ago, and its performing fine. Then I installed this one
p.jpg

Brand New SQLF30A Bridge Rectifier 3-Phase Diode 30A 1200V
( 400714167691 )

($3.65 from dealbestshop in China) in my '75, and it makes me a bit nervous, altho it is functioning well at the moment. It might be one of those "super-cheap" and fragile items.

That's exactly what I am running and I have had no problems with it. After I got everything up and running I thought, what the heck at $3.65 a pop, why not go crazy and order a couple more! And that's exactly what I did. I don't expect it to fail but if it ever does , I've got a couple back ups!

And oh yeah, I'm running an automotive VR-115 with that.
 
That's exactly what I am running and I have had no problems with it. After I got everything up and running I thought, what the heck at $3.65 a pop, why not go crazy and order a couple more! And that's exactly what I did. I don't expect it to fail but if it ever does , I've got a couple back ups!

And oh yeah, I'm running an automotive VR-115 with that.
I've got a "couple more" of so many parts, but for some reason I failed to get a couple more of those..:laugh2:
And the seller no longer has any...
But I've still got a couple more Radio Shack rectifiers.

Am I correct, Bob, that if this Chinese bridge rectifier goes bad, the symptom will be that charging will drop down from the usual charging rate?
 
I've got a "couple more" of so many parts, but for some reason I failed to get a couple more of those..:laugh2:
And the seller no longer has any...
But I've still got a couple more Radio Shack rectifiers.

Am I correct, Bob, that if this Chinese bridge rectifier goes bad, the symptom will be that charging will drop down from the usual charging rate?

You know, I’m not really sure how a failure would present itself. When I installed that unit , it was because I was trying to fix a non charging system, and after bench testing the various components I found the rectifier was no good.
I decided to replace the voltage regulator also, just to drag the whole system into the 20th century.
Btw, even if the supplier you bought that one from doesn’t carry them any longer they are available from multiple vendors on eBay. They are pretty common.
 
Daniel Black was the one who had problems with these cheap rectifiers, don't know why. I don't recall anyone else reporting them. The next "step up" is the $10 Windy Nation offering .....

https://www.windynation.com/Rectifier/35-Amp-3-Phase-Bridge-Rectifier/-/218?p=YzE9MjA=

Daniel tried one of them and I don't think he's had any problems since. That's what I have and it's been trouble-free since I installed it several years ago. I do have a couple of those cheapies though as back-ups. Windy Nation offers theirs in a 5-pack too. Then they're only $6 each. If I had more bikes, I might consider that.
 
Thanks 5T, I recall now it was Daniel, and RG continued to make commentaries about those "bad, cheap" rectifiers.

The beauty of them wasn't just the low price and free shipping, but they had the built-in heat sink.
This item seems to be identical:
https://www.ebay.com/itm/3-Phase-SQ...-5-Terminals-Diode-30A-1200V-New/181422558219
s-l500.jpg

What do you think of it? Its a little over 6 bucks. Free ship.

>And about my question as to the symptoms if it fails; would we simply witness a decline in charging rate?
.
.
 
Yes, the charging rate will decline or possibly stop completely, depending on how many of the diodes in the rectifier have gone bad. These 3 phase rectifiers contain 6 diodes wired up in pairs. One of the white wires from the alternator connects in between each pair. If one pair of diodes has gone bad, you'll only get about 2/3 of the charging output, 2 pairs about 1/3, etc.

Diodes are like one-way filters or "gates" for current flow. The AC, or alternating current being fed in on the white wires flows back and forth, or in both directions. The diode pair only lets one direction of that current flow through. So, what you get coming out is DC current flow. Here's an excerpt from an early manual that explains it pretty well .....

4y3Fzjy.jpg


I see nothing wrong with these cheap units, as long as a rash of failure reports don't start cropping up. The fact that they come built on a heat sink already is one of the things that attracted me to them. There is another option, a unit used on some other Yamaha models, the XS500 in particular. This is a more modern, totally sealed unit and looks quite nice. All that is required for 650 use is changing the plug, female to male connectors .....

IkRVXeK.jpg


gwHCW6m.jpg
 
Yes, the charging rate will decline or possibly stop completely, depending on how many of the diodes in the rectifier have gone bad. These 3 phase rectifiers contain 6 diodes wired up in pairs. One of the white wires from the alternator connects in between each pair. If one pair of diodes has gone bad, you'll only get about 2/3 of the charging output, 2 pairs about 1/3, etc.

Diodes are like one-way filters or "gates" for current flow. The AC, or alternating current being fed in on the white wires flows back and forth, or in both directions. The diode pair only lets one direction of that current flow through. So, what you get coming out is DC current flow. Here's an excerpt from an early manual that explains it pretty well .....

4y3Fzjy.jpg


I see nothing wrong with these cheap units, as long as a rash of failure reports don't start cropping up. The fact that they come built on a heat sink already is one of the things that attracted me to them. There is another option, a unit used on some other Yamaha models, the XS500 in particular. This is a more modern, totally sealed unit and looks quite nice. All that is required for 650 use is changing the plug, female to male connectors .....

IkRVXeK.jpg


gwHCW6m.jpg
Thanks 5T,
That is exactly the info I've been looking for. Now, I'll be less nervous this spring when I take the '75, the one with the cheap Chinese unit, far from home.
 
I am using the "cheap Chinese unit" on a Honda. Works great, great fix, great price. It doesn't take much to give a product a bad rep on the internet. I don't care for too many push connectors, so I used ring connectors, small screws, lock washers, nuts and shrink tube to connect to the rectifier.

Scott
 
5twins,
where are you getting your connectors from?
 
I started out with a couple kits from this place, and their crimping tool. I got a kit for bullet connectors and one for multi-spade connector blocks .....

http://vintageconnections.com/

I've supplemented the kits with more connectors, mostly from eBay. Those are Chinese so the quality isn't quite as good, but I got them mostly because they included the plastic insulator sleeves and were dirt cheap, lol. The silver female spades shown above came from McMaster-Carr and are very nice, but they are "stand alone" crimps. They don't have the little locking tab that locks them into connector blocks .....

9juXLtL.jpg


But that's OK. Sometimes that type is just what you need. Above, I combined them with the plastic insulator sleeves from the eBay crimps.
 
I have found the quality of the connectors and the pricing at Vintage Connections to both be excellent.
The fellow who runs the store seems to be doing it mostly for the love of motorcycling.
 
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