Faulty Stator perhaps?
Re: Faulty Stator perhaps?
Thank you gentlemen for your input.
So, with the parts on the bench, including the battery of course, I have 12 volts from the stator to the regulator. If the regulator passes this straight through, as it appears to be doing, this would seem to indicate a faulty regulator from what you say.
On the other hand, it is a brand new AO regulator which passes all the diode checks done on it.
There have been no comments on my suggestion about the stator only being connected to the battery after the key is ON and taking the regulator output straight back to the battery. Is that because it is too idiotic to consider and, if so, why?
Anybody got a good working Morini regulator they would be prepared to lend me to check things out?
So, with the parts on the bench, including the battery of course, I have 12 volts from the stator to the regulator. If the regulator passes this straight through, as it appears to be doing, this would seem to indicate a faulty regulator from what you say.
On the other hand, it is a brand new AO regulator which passes all the diode checks done on it.
There have been no comments on my suggestion about the stator only being connected to the battery after the key is ON and taking the regulator output straight back to the battery. Is that because it is too idiotic to consider and, if so, why?
Anybody got a good working Morini regulator they would be prepared to lend me to check things out?
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Re: Faulty Stator perhaps?
An Al Osbourne regulator? They are for dynamo systems only, your bike has an alternator. I'll take look at AO website to see if they do what you need, which is s rectififer/regulator.
EDIT! OK ignore what I said above-AO do the right thing nowadays so panic over. (My panic that is)
EDIT! OK ignore what I said above-AO do the right thing nowadays so panic over. (My panic that is)

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Re: Faulty Stator perhaps?
The other option being that the diodes are back to front and passing current through to the regulator! However, I do not have a wiring diagram for the rectifier and no idea how it works. There may be one on the nederland club pages accessible from this site.velojames wrote: ↑13 Oct 2025 09:21 Thank you gentlemen for your input.
So, with the parts on the bench, including the battery of course, I have 12 volts from the stator to the regulator. If the regulator passes this straight through, as it appears to be doing, this would seem to indicate a faulty regulator from what you say.
On the other hand, it is a brand new AO regulator which passes all the diode checks done on it.
There have been no comments on my suggestion about the stator only being connected to the battery after the key is ON and taking the regulator output straight back to the battery. Is that because it is too idiotic to consider and, if so, why?
Anybody got a good working Morini regulator they would be prepared to lend me to check things out?
All I know is how mine operates.
Edit:
Is this the one? http://www.aoservices.co.uk/products/a-reg.html
Re: Faulty Stator perhaps?
I believe with the standard reg. rect. the stator windings are live all the time even with the engine not running and the key out. Some people used to introduce fuses in case of faults.
Donkey's years ago I did sit outside a pub with some other MRC members and watch as my bike stated to smoke from the air ducts around the stator and later found that it was the dodgy old stator I had fitted, which decided to short to "earth" as we sat in the beer garden admiring the Morinis. The stator cooked itself and I had to fit a better one, no problems ever with that one. My point though; As it was live all the time it was possible for it to do what it did.
Donkey's years ago I did sit outside a pub with some other MRC members and watch as my bike stated to smoke from the air ducts around the stator and later found that it was the dodgy old stator I had fitted, which decided to short to "earth" as we sat in the beer garden admiring the Morinis. The stator cooked itself and I had to fit a better one, no problems ever with that one. My point though; As it was live all the time it was possible for it to do what it did.
Re: Faulty Stator perhaps?
Thanks Bumblebee,
That must have been a moment of panic I daresay.
It seems that it has been firmly established that the stator is always live and that 12 volts appears on both yellow leads whether the bike is switched on or not. Now, my new and double checked regulator is passing this straight through. Do original Morini regulators (Ducati?) not do this? Now I am not sure if my regulator is OK or not.
Anyway, thanks to everyone who has sent advice. I will have do do more thinking.
That must have been a moment of panic I daresay.
It seems that it has been firmly established that the stator is always live and that 12 volts appears on both yellow leads whether the bike is switched on or not. Now, my new and double checked regulator is passing this straight through. Do original Morini regulators (Ducati?) not do this? Now I am not sure if my regulator is OK or not.
Anyway, thanks to everyone who has sent advice. I will have do do more thinking.
Re: Faulty Stator perhaps?
Missed the additional query from Mickey about the make of reg. Yes that is the one. I believe I mentioned earlier that the wiring is Not according to the incomprehensible Morini diagram but to one of Rupert Paul's diagrams.
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Re: Faulty Stator perhaps?
Electric Start models have an in line fuse. The battery is connected to the starter solenoid and is teed via a fuse to the fuse box and teed to the ignition switch and alternator. Yes, the windings are live all the time, bear in mind before removing the stator. Don't ask me how I knowBumbleBee wrote: ↑13 Oct 2025 12:25 I believe with the standard reg. rect. the stator windings are live all the time even with the engine not running and the key out. Some people used to introduce fuses in case of faults.
Donkey's years ago I did sit outside a pub with some other MRC members and watch as my bike stated to smoke from the air ducts around the stator and later found that it was the dodgy old stator I had fitted, which decided to short to "earth" as we sat in the beer garden admiring the Morinis. The stator cooked itself and I had to fit a better one, no problems ever with that one. My point though; As it was live all the time it was possible for it to do what it did.
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Re: Faulty Stator perhaps?
The Morini diagram is quite simple. Just need a magnifying glass!
Re: Faulty Stator perhaps?
With the standard system; When the ignition is off and the engine isn't running the voltage from the battery comes through the standard reg. rect. and imposes itself onto the stator (Yellows and Red). It doesn't reach the part of the stator thats for the ignition (Green and "Earth") that is a totally separate system that runs on much lower voltages and would be damaged by battery voltage.