The alcohol definitely makes a difference in the way these things run.Stations here around Houston advertise 10% ethanol, it's closer to 20% usually according to Yamaha and Honda from test results they've had figuring out problems on bikes. Fuel mileage goes down as well. I try to leave the tank a little low if I know I'll be in outlying areas that sell straight gasoline. ( BTW, don't leave that crap in your lawn equipment long without running it, the alcohol eats up the insides of the carb. All my lawn stuff runs on Sunoco 110 lowlead with Blendzall, lol)