Bike Rental in Italy - Venice area ?

[JBL]

Hi all. Can't really say more than the title.

I am off for 3 weeks in Italy in June next year with work. However, I'll be free at the week ends so I was thinking of renting a bike and go exploring the surroundings... possibly riding up North to find some mountains. (Stelvio Pass is "only" 370kms away )

Does anybody know of a good address from where to rent a motorbike in the Venice area?

Thanks.