So I did my weekend ride and have some numbers.
My around town, to work and home 100% town driving, was terrible running ethanol free premium octane, got me 29.8.
The trip I did was almost all freeway to first fuel stop, got me 37.9 mpg on 10% ethanol premium at about 70-85 mph speed
From there to second fuel stop it was up and over a mountain pass, lots of twisties running about 50mph-65mph I got an astonishing 47.1mpg on 10% ethanol premium
From second to third fuel stop It was more freeway but only about 65mph-75mph and got 41.9 mpg on 10% ethanol premium
All of this is in my fuelly info in my sig, but its not displaying it all very well for some reason. Go here -->
2008 FZ1 (Yamaha FZ1) | Fuelly
Anyways, hope it helps. My bike is stock besides slip on exhaust, Zero Gravity touring screen and I did have all 3 pieces of my GIVI luggage on the bike loaded up, about 15-20 lbs extra weight, but the side cases to stick out a bit so possibly some wind drag from them as well.