If your running AT like the Duratrack, thats part of the problem.2022 with 5,000 miles. The best I can do is 17.5mpg on the highway with a real soft touch doing about 70. Around town 15 to 16 mpg, again with a soft touch.
Maybe a less aggressive tire would help???
It helped for me, but not eveyone agrees with a more streetable mileage tire on the Rebel.