When i was in Italy 2 years ago gas was 1.29 a liter and after 3 summers in a row in Italy <2004,5,6> the only time i saw large bikes was a very few times,i remember up in the mountains seeing a couple of brand new triumph SPEED TRIPPLE probably rentals.
The only time i saw large bikes was on weekends around Verona Harleys and such most were owned by guys that were US military and they mostly road to the center of town parked and drank all day,kinda like over here in the states.