I once had a regulator rectifier go on me in spectacular fashion on an old Suzuki I had.
Took the Mrs out for a spin when...
Just riding along normally when loads of smoke started billowing out of the bike, we stopped and before I had even got off the wife had dialed 999 for the fire service
They wern't impressed when they turned up to see the tiny bit of remaining white smoke coming out.
To be fair she did really smoke and it was worrying for a second.
The garage explained that it was the Rectifier and changed it straight away, apparently Suzuki designed it to go in a stupid place, right at the front where it got covered in muck all the time and it just corroded away!
The moral of the story I guess is that if it was the Rectifier, considering your V just gave up suddenly, you'd know if it was the Rectifier.
Good luck and hope all turns out well!