yes it is legal. There is no law anywhere that says duck tape can not be on the helmet period. Actully i used to do that when i was racing just to make sure the visor was secure in the down postion. hah wouldnt want the visor to flip up when goin 150+ around turns.
But yeah it is completly legal. If you would like proof of this, search the web for " *you state* motorcycle safety laws"
then browse websites like that.
