Doubting my mechanic...

silverbullet132 said:
Found out today that every light bulb in the bike (headlights, signals, break lights) are ALL over voltage from stock (some not by much). Will be replacing all of them then going from there.
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What do you mean "over voltage"?
 
slowbird said:
I have swapped out alot of my bulbs (brakes, signals, Intrument cluster) to LED's and that has cut down on alot of the drain.
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Do you realize by added LEDs you are making the R/R work harder? Unlike a car, most motorcycles charging systems generate 100% power and short what is not needed to ground.

The stock R/R is fine IF you have good grounds and contacts. Every old bike needs the connections cleaned up. My R/R is now 7 years old.
 
Franko! said:
Do you realize by added LEDs you are making the R/R work harder? Unlike a car, most motorcycles charging systems generate 100% power and short what is not needed to ground.
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I mention the LED installation in response to silverbullet mentioning dimming lights.
The LED's have cut down alot on the draw on the electrics. I have a voltage "gauge" and can see the bike holding a nice consistant charge even with brakes applied and signals flashing.

I have no worry about any extra strain on the R/R as I have a good aftermarket one and a beefy VFRness installed.

Franko! said:
The stock R/R is fine IF you have good grounds and contacts. Every old bike needs the connections cleaned up. My R/R is now 7 years old.
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The stock R/R is just that...fine. But the aftermarket and upgraded ones are better...the finned ones help dissapate heat better. But yes, the connections are a big issue with the burnt wiring and harnesses.

silverbullet132 said:
No, none of the stock plugs were used. All connections were soldered.
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Really?

Go here: http://www.wiremybike.com/index.php?cPath=1_8 and get a VFRness and R/R that will just connect into what you got.

The VFRNess is well made.
 
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Franko! said:
Do you realize by added LEDs you are making the R/R work harder? Unlike a car, most motorcycles charging systems generate 100% power and short what is not needed to ground....
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Not True.

Modern street bikes charging system is designed EXACTLY the same as a modern car.
The last bike that had a zener diode, that leaked to ground (intentionally) was a Norton.
If it has a regulator, all alternators do, they don't make the excess power that has to drained/leaked off to ground.
 
bitzz said:
Not True.
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Yes, unfortunately it is true.

Modern street bikes charging system is designed EXACTLY the same as a modern car.
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No, they aren't. In fact very few bikes use an automotive style alternator. Gold Wing, for example.

The last bike that had a zener diode, that leaked to ground (intentionally) was a Norton.
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A single zener diode used to be a common method for regulating smaller single phase systems. The '98 VFR (for example, but typical) has a 470 Watt 3 phase stator. The Rectifier / Regulator does just that; a 3 phase rectifier and a Voltage regulator built into the same device. A typical automotive regulator only regulates the Voltage, by varying the Voltage on the field windings, the rectifier is built into the alternator.

If it has a regulator, all alternators do, they don't make the excess power that has to drained/leaked off to ground.
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Unfortunately, this is not how most motorcycle charging systems work. The R/Rs are "shunt" regulators, meaning they shunt (or short circuit) to control the Voltage output. While this isn't a very efficient or elegant method, it is small, light and has only one moving part; the magnets spinning on the end of the crank shaft.

There are a few "series" style R/Rs coming onto the market. These are quite interesting. They have the no moving parts and smaller/lighter advantage of the existing system without the abusive shunting of the stator.
 
Probably the easiest way to describe the difference is that (most) motorcycle alternators use permanent magnets on the rotor, so they will always generate power, which has to be dissipated (by the R/R) if not needed. Automobiles use coils on the rotor with slip rings to supply power only in the amount that is needed to generate the power required to keep the system balanced. Cars can therefore generate more power at lower revs than the old generator systems, and cut it back at higher revs so that the system does not melt. SOME higher priced and/or exotic bikes have wound rotors instead of magnets, but that is a far more expensive system, so not typical. And yes, the LED lights put more strain on the R/R as it has more power to dissipate. Strange but true. And the zener was used on the Norton because Lucas had a 3 wire diode bridge at the alternator that was not capable of regulating voltage, only rectifying.
 
VFR.CBR said:
Yes, unfortunately it is true.



No, they aren't. In fact very few bikes use an automotive style alternator. Gold Wing, for example.



A single zener diode used to be a common method for regulating smaller single phase systems. The '98 VFR (for example, but typical) has a 470 Watt 3 phase stator. The Rectifier / Regulator does just that; a 3 phase rectifier and a Voltage regulator built into the same device. A typical automotive regulator only regulates the Voltage, by varying the Voltage on the field windings, the rectifier is built into the alternator.



Unfortunately, this is not how most motorcycle charging systems work. The R/Rs are "shunt" regulators, meaning they shunt (or short circuit) to control the Voltage output. While this isn't a very efficient or elegant method, it is small, light and has only one moving part; the magnets spinning on the end of the crank shaft.

So far the only difference you have described is that motorcycles have the regulator and rectifier built into one box. Still two VERY separate entities, doing two very separate tasks. Motorcycles also contain the motors and transmissions in one case, unlike a car. Are the motors and transmissions on bikes one entity also then?
Car alternators have the regulator and rectifier in one box also. It is called the alternator. Is this alternator one entity?
Car alternators have only one moving part; the rotor.
In a car alternator the regulator "regulates" the output of the stator by controlling the magnetic flux of the rotor through the "field"... just like on your VFR.
In a car alternator the rectifier takes the three phase AC current off the stator and runs it through a series of diodes (three negative and three positive on separate plates... just like your VFR) to get a 12volt DC current; just like your VFR does.


There are a few "series" style R/Rs coming onto the market. These are quite interesting. They have the no moving parts and smaller/lighter advantage of the existing system without the abusive shunting of the stator.

There never were moving parts in a rectifier and no one has used a mechanical regulator for many years... meaning modern car regulators have no moving parts either.
... oh and the stator doesn't mind shunting. The problem of shunting is usually dealt with in the rectifier with avalanching diodes in a modern system and the problem is excess heat... just like on your VFR
...oh and you don't "shunt" the stator, you "shunt" the excess output of the stator, usually with the rectifier (as previously noted) or in rare cases with the regulator.
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So I will reiterate: A modern bike's charging system is EXACTLY the same as a modern car's charging system... they just moved some of the parts around. Point to any part of a modern bike's charging system and I will point to the equivalent part on a modern car's charging system. (It's not my fault that the bike manufacturers make you buy both a regulator AND a rectifier when either part craps out).
If you understand what is happening in a charging system it is easy to see.
 
skapan said:
Probably the easiest way to describe the difference is that (most) motorcycle alternators use permanent magnets on the rotor, so they will always generate power, which has to be dissipated (by the R/R) if not needed. Automobiles use coils on the rotor with slip rings to supply power only in the amount that is needed to generate the power required to keep the system balanced. Cars can therefore generate more power at lower revs than the old generator systems, and cut it back at higher revs so that the system does not melt. SOME higher priced and/or exotic bikes have wound rotors instead of magnets, but that is a far more expensive system, so not typical. And yes, the LED lights put more strain on the R/R as it has more power to dissipate. Strange but true. And the zener was used on the Norton because Lucas had a 3 wire diode bridge at the alternator that was not capable of regulating voltage, only rectifying.
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The reason cars use a wound stator is you can get more power out of a wound stator. Using permanent magnets is not as efficient. To get 130 amps out of permanent magnets the alternator would be HUGE... the size of a small V6. Valeo and Denso make a 130 amp alternator that is 4.5 inches in diameter.
Bikes don't need big alternators so they get cheaper to build permanent magnet alternators.
Nortons had zeners because they had NO regulation of the output, the zener WAS the regulator. If the alternator output more than 14 volts the zener would dump the output. In a modern system the output is regulated so the output is not higher than 14 volts... unless there is a problem. If there is a problem and the output of the stator is too high it gets dumped by avalanching diodes in the rectifier... or just burns everything and toasts the battery (sound familiar Suzuki guys?)
An Ex500, not an expensive motorcycle, has a permanent magnet rotor and a wound stator with no slip rings on the rotor. How?
The output is regulated through the stator. Same as regulating the rotor. More power in, gets more power out.
It's just magnets moving in electrical flux. It doesn't matter if the magnets move or the magnet flux moves... same end result; the magnets push/pull electrons down a wire.
SOOOOOOOOooooooo if you regulate the rotor you have to have slip rings and if you regulate the stator you don't.
The reason we all went to alternators and away from generators is an alternator is more efficient and easier to regulate.
LEDs do not put more strain on a regulator, the rectifier doesn't care, all the regulator is trying to do is balance load with output.

Unless there is a problem with the modern system there is no excess power to shunt. That is why we have regulators.
 
I'm going to respectfully disagree with you here, bitzz. On most modern Honda scoots at least, the alternator is a permanent magnet rotor, wound stator affair that is constantly producing power. This power is sent to the battery until said battery reaches the zener's rated voltage, at which point the SCRs are turned on and ALL of the stator's output is then shunted to ground. The heat generated by the SCRs during the shunt process is typically the reason for the R/R's failure.

Here is a diagram of the typical OEM Honda regulator/rectifier package:
voltreg.jpg
As you can see, there is no circuitry adjusting the field strength of the stator field, the output is simply redirected by the regulator section. My '82 Nighthawk did have a wound rotor that was controlled by the regulator and it worked great as long as the rotor was not overheated. I suspect manufacturing costs were a large contributing factor in Honda's decision to move to a permanent magnet layout.
 
silverbullet132 said:
No point in that now. All the stock connecters from the stator/ R/R were cut off. The stator is soldered into the R/R connector and the R/R output goes straight to the battery. To use a VFRness I would have to cut that all up and buy new connectors on top of the VFRness.
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Assy. well I can understand why your Mechanic wants to go back to stock. Sometimes when trying to track down a problem, starting from scratch is the best way to go.

Is the R/R from a VFR or just some random bike?
 
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