Hmm... my Shimano hub doesn't have any vibration at any meaningful speed. I can feel it when holding up the bike and spinning the wheel by hand, though.
Originally Posted by
quester
It seems to max out at around 14 mph, slowly waning at higher speeds.
Are you saying that it has the most vibration at 14 mph?
It totally cuts out when I take the charger out of the circuit. This is the Busch and Muller "Ride & Charge".
I'll guess that the charger draws a bunch more current, which manifests itself as more force against the magnets in the hub.
I don't have a charger like that, however, and don't notice any ill effects from the dynohub that aren't overwhelmed by various gusts and breezes blowing against me.