Strange as it sounds, I'd ask those who are the best at Burgman 400 (look up in the vehicle database), because what you're aiming for is to be among them, based on fuelly (and Spritmonitor) logs. I'd say that you should keep your highway speed down and minimize brake use by keeping more distance behind other vehicles and timing lights in the cities, but to be the best you'll probably need to know the perks of the very model you ride. Especially the automatic transmission it has, because it might have some ideal cruising speed and rate of acceleration. Or tricks to get lower rpm at the same speed. Or anything else I don't even think about
I think you might be reaching too high for 80 MPG. Unless of course you are coasting downhill. The best I got on my BV500 was 136 mpg... up from Reno, then downhill over the Sierra crest. My average is about 61. Keep up on the tire pressure, and no jackrabbit starts..