|
|
|
Starting Member
Group: Forum Members
Last Login: 1/11/2006 5:11:13 PM
Posts: 14,
Visits: 0
|
|
I have found a stator that matches my bike and the description states it has a higher output at low and high rpm(no tech details given), do you think the originaly installed rectifier/regulator will work well with the higher output stator?
A 1984 honda magna 700cc vf700c
|
|
|
|
|
New Member
Group: Forum Members
Last Login: 7/29/2008 6:11:58 PM
Posts: 79,
Visits: 22
|
|
quote:
Originally posted by dlsmith
I have found a stator that matches my bike and the description states it has a higher output at low and high rpm(no tech details given), do you think the originaly installed rectifier/regulator will work well with the higher output stator?
A 1984 honda magna 700cc vf700c
Without much more to go on, it may work but then again it may cause problems.
The permanent magnet alternator/shunt regulator system on these bikes is a work of cost cutting art of the highest order.
The stator and the regulator are designed to work together. At a certain point in the AC waveform, the regulator switches a short circuit across stator leads in the proper sequence to regulate the voltage to a maximum value. The stator produces three phase balanced alternating current. The rectifier operates to rectify and add the three phase currents and the result is a DC current.
Here's where the trick comes in The winding resistance of the stator is relied upon to dissipate most of the losses caused by the regulator's intermittent short circuit of the stator leads. In the process, the maximum short circuit current into the regulator is limited by the stator resistance.
So, the maximum stator current output ALSO is limited by the stator resistance, among other things. Dumping a lot of waste energy into the stator causes no problem, because most motorcycle stators are oil-cooled, and placed in a location where large quantities of oil flow around it.
The so the new "higher output" stator may have a beefier winding, which would supply more load, but which also at light loads would cause more current to flow in the regulator portion of the regulator/rectifier.
So here's a tip for you to look at. Find a way to measure the temperature of the regulator rectifier with the old stator and the minimum electrical load. When you install the replacement stator, do the same measurement and see how much if any the temperature increases. If it's more than 10 deg. C or so then you might be concerned.
On the other hand, perhaps you can purchase a new regulator that is designed to work with the new stator. That would be the best choice.
|
|
|
|
|
Starting Member
Group: Forum Members
Last Login: 1/11/2006 5:11:13 PM
Posts: 14,
Visits: 0
|
|
thank you for your time...i can see that without more tech details of the system one would have to do carefull testing to figure out the unknowns
|
|
|
|
|
Junior Member
Group: Forum Members
Last Login: 10/20/2007 10:20:59 AM
Posts: 169,
Visits: 31
|
|
Shunt regulators as you said are the epitome or cost cutting and a sorry way to regulate. The older Hondas all had the same type. In the shop manual it called it (in Jenglish) a pointless regulator. Which was in a sense true but shoddy would have been better. And people wondered why the stators went bad. If they stop shunting your battery boils away. If they work your stator burns up. If the stay shunted your battery is drained. It is a lose/lose/lose situation. A friend and I are working on a prototype replacement for those types. It should be universal needing only harness adapters for different bikes.
Ben Kirk
ahondanut
'72 CL450/'73 CB450
'85 CB650SC
'03 ZRX1200R
Ben Kirk
rnrkeeper
'72 CL450/'73 CB450
'85 CB650SC
'03 ZRX1200R
|
|
|
|