How far can I go?

I did a 180 mile blast to leeds from Oxford and didnt use the whole tank. The fuel indicator light was on but flashing so still a fair few miles left in the tank. I was doing between 75-90mph depending on traffic, so a steady 70 should see you doing 200 miles plus easily. I do have a double bubble, and spend most of the ride lying on a tank bag to get out of the wind - I'm not sure how much more efficient a flip screen makes the bike, not too much i imagine.