I just installed these Saturday in my OHV, and i went from about 18 mpg highway to about 23 when I checked it today. And mixed driving went from less than 15 to 17-18 mpg. I will see how these perform during the week as I have been getting less than 12 mpg around town. These calculations were based off filling the tank and driving, and filling again. I used a GPS system to tell me how fast I was going and from there I got the percentage of error for my tire size and calculated actual mileage from that. My 23 mpg was all highway except for about 10 miles, of which some was up mountains and some city driving. My highway driving was at a higher than normal speed due to people driving like maniacs today, but I was highly impressed. Whether theres more power or not, it feels it, I felt like I didn't downshift anywhere near as much when climbing slight hills on the highway. So far I like them.
Dan