Call me a wimp but my arse generally needs a break before 4 hours of ride time are up, though depending on speed I can get 4+hours of range on my Kawasaki with just it's standard fuel tank (which is just about 7 gallons - things are a bit top heavy after a cillup @ the pump)! I usually get ~ 250-260 miles before hitting reserve, which give me another 40 miles if I'm careful.