Just stranded. Voltage Regulator Rectifier Smoking :-(

[system9]

Ok,
what is the best aftermarket reg/rec for 80+ with a Pamco or TCI?
And: If price didn't matter
Just wondering.

I wanted a Reg/Rec that would work on an 81 with a PAMCO and PMA after my new one fried after 2 days.
I was willing and ready to build my own, but the DIY Reg/Rec plans were all for the stock charging system. I asked how to build one for a bike with PAMCO and PMA and got no reply, so I did research and finally decided on the Shindengen FH020AA with an inline Circuit breaker and Furukawa weather proof connectors. Shindengen has been making Reg/Rec units for Yamaha and many other bikes for years. To me, if something is $35 and fails, it is not cost effective at all. If it costs $100 and lasts the life of the machine with no worries, then its worth every penny.
I have been putting my bike through the paces, so far so good, but only time will tell.

 

[retiredgentleman]

Very wise on your part to buy the Shindengen rec/reg, since its Japanese quality. However, if I'm correct, you still have a chinese made stator. The stator is now likely to be the weak link.

 

[system9]

Very wise on your part to buy the Shindengen rec/reg, since its Japanese quality. However, if I'm correct, you still have a chinese made stator. The stator is now likely to be the weak link.

Correct. So far the PMA has been working well. If my new PMA stator does fail prematurely I have a feeling that I may go back to the stock rotor and brush setup, which I removed very carefully and have kept in a safe place. At that point I would probably try to build my own Reg/Rec.

 

[retiredgentleman]

The stock alternator design (energized rotor) is the best choice for these bikes. A second choice would be a PMA, buy only if you use all Japanese components. Unfortunately most lads buy the chinese, aftermarket PMA parts, and then suffer with premature failures.

 

[5twins]

PMAs are common and stock on many other bikes. Unfortunately, even with their stock better quality Japanese parts, many still burn out stators and regulators. The Shindengen seems to be the upgrade reg/rec of choice but it can't be had cheap. I too am very glad our 650 has a common automotive style charging system instead. That's what makes it possible to use low priced (but good quality) automotive regulators. Once you learn a little about the stock system, learn about the two types used and the corresponding regulator each requires, it's easy to find automotive replacements. Besides the couple frequently mentioned here (VR115, VR295), there are many others that will work.

The 650 and automotive charging systems basically come in two "flavors". They are pretty much the same but differ in how they are wired up. One type permanently grounds one of the brushes inside the alternator and the regulator feeds "regulated" power to the other brush. It turns the power on and off and that effectively shuts the alternator on and off, controlling it's output. The other type constantly feeds switched power to one brush in the alternator and the regulator switches the ground on and off to the other one.

These two types of regulators have even been given names or designations. They are called either an A type or a B type circuit. A regulator with the A type circuit switches the ground on and off. A regulator with the B type circuit switches the power on and off. 650s up to '79 need a power switching or B type regulator. '80 and later 650s need a ground switching or A type regulator. Once you know what to look for, you have many choices. I recently stumbled across this one on eBay. It is the A type so is suitable for the later charging systems. What I like about it is the look and the price. It's much nicer looking than the plain tin box kind. Nice enough that I think you could even mount it externally on a custom build and it wouldn't detract from the looks. I think it looks cool. And then the price - they can be had for $10 to $12 .....

 

[Signal]

5twins that info on the A and B circuits is golden. I have a 750 triple in need of a regulator and your post will be very helpful when I get to sorting it out. Thanks.

 

[5twins]

Interesting. I took a quick look at an early 750 triple shop manual. It uses pretty much the same charging system as the early 650s. It uses the exact same mechanical voltage regulator. That makes it a power switching type B unit. Detailed instructions for adjusting the regulator are given in the manual, even more detailed than what's given in the 650 manual. Also of note, it says the regulator output should be checked (and adjusted if need be) every 8,000 miles. There is no mention of a check interval in the 650 manual.

 

[Signal]

You keep doing my homework!. Info cut and pasted for future reference. Thank you again

 

[littlebill31]

Thanks, 5twins. Great explanation.
I just bought one to have incase mine goes up. Possibly will change them out this winter anyway. I do like the nice aluminum look too.

 

[littlebill31]

Just wondering here, as I am electrically challenged.
How would you wire the Shindengen FH020AA to a stock system? Seems that the G and Br wires on the stock system brushes/rotor aren't on the pictured unit. Or is is not compatible with the stock system.

 

[5twins]

I don't think it's compatible with our stock systems. It's made specifically for use on PMAs. And besides, it costs an arm and a leg, lol.

PMAs work differently than our stock systems. Their regulators don't turn them on and off to control the charging output. Basically, they run full blast all the time. Well, not exactly full blast, their output is RPM related just like our systems, but they don't get switched off if charging output is higher than needed. Instead, they "shunt" or bleed off that excess charging through the regulator. In fact, the regulators are called a "shunt" type. This is where the problems start. That excess charge is bled off in the form of heat and some is also fed back into the stator to get bled off. That heats it up more too. That's why PMA stators and regulators burn out. If you ask me, I think the whole PMA set-up is a piss-poor design.

There are new type series regulators that have recently come out for PMAs. They are more like the regulators on our stock systems. They don't divert as much excess power back into the stator and they run cooler. But they cost even more than the normal shunt type PMA regulators. It all strikes me as quite a racket. I wish I owned stock in a PMA regulator company, lol.

 

[littlebill31]

Thanks, 5twins.
Again, great info.

 

[retiredgentleman]

Yeah 5twins.....................selling PMAs is a real racket. All the aftermarket guys (Mikexs, HHB, xsCharge, etc, etc,) buy those chinese PMAs in large quantities, and likely make 100% or more profit. The manufacturer makes money, the aftermarket guys make money, so its a win/win situation.........................oops, I forgot the buyer gets ripped off.