See post #52of this thread.
It's one other reason the manufacturers did not install voltmeters.
Another is probably the fact that they would have to explain to owners that anywhere from 13.5 to 14.8 Volts was normal, depending on rpm and load.
If you are using an regualtor with electronic guts, and the alternator is good, then probably all you're seeing is the regulation in action or the ripple.
As the engine speeds up the alternator can produce more power and it also the ripple frequency increases so its no longer as noticible.
