I picked up my 2014 R3T in April of 2018 with 2,777 miles on the odometer. I bought the bike in San Antonio, TX and rode it 1,200 miles back to Florida. I averaged 31.5 mpg with the worst being 24 mpg and the best being 33.6 mpg. This was all on the interstate traveling 80-85 mph. At one point I got up to 94 mph passing some slower traffic.
Since then I have ridden 11,431 miles in about 4.5 months. The motor, exhaust, and intake are stock. I ride mostly on 2 lane, rural roads and a little in-town. My speeds are generally 45-65 mph. When on the interstate I will do 80-85. The worst I have gotten was 29.1 mpg and the best was 40.1 mpg. I average 34.1 mpg with a standard deviation of 2.3 mpg. This means that on average I should get between 29.5 and 38.7 mpg. I also try to use only top tier gasoline or non-ethanol gasoline. I have found that I get better fuel economy with top-tier gasoline compared to non-top-tier gasoline. Non-ethanol gasoline has been giving me a little better mileage than top-tier gasoline. I record all my fill-ups in a spreadsheet and am tracking the fuel mileage among the different brands of top-tier gasoline and the non-ethanol gasoline in my area.