I rode from Washingto to California through Oregon and I noticed about a 10% decrease in mileage as soon as I got gas in CA. Ethanol. Also, I noticed about a .60 cents decrease in price as soon as I crossed from WA to OR. They say the west coast has high gas prices because of refining. Bullisht. Its taxes and manipulation.

 

you use more ethanol gas per mile.Check different stations.

 

I've ridden in many states and I haven't found any gas that isn't at least 10% ethanol. Not anywhere. My mileage dropped from 47-48 to a consistant 40-42. I don't follow the logic of gasahol. If you get 10% less mileage you need 10% more fuel to travel the same distance which results in 10% more polution. Go figure.

 

The corn people dont give a isht about your mileage or the air. They just want to sell more corn for more money. period. to hell with whoever doesnt like it. Thank Archer Daniels MIdland and Nebraska/Kansas/Iowas\ senators.

 

From 46 to 42 is about 9% difference. A couple of things quickly come to mind. First is that the newer tires will actually roll further per revolution than those which came off. Of course, this will affect things proportionately, but you might be rolling so much further (haven't done any possible math scenarios) now that in reality you're still getting about as many true miles per gallon as before. Before the change you were undoubtedly indicating more miles than you were really traveling. At least more than you are now.

The second thing is the effects of oxygenated fuels, which has already been mentioned. Ethanol is an oxygenate as well as offering fewer BTUs per gallon. You will typically use about 6% more of it than straight gasoline. I personally wouldn't mind that if it cost that much less, but that's usually not the case, so using it does result in a financial loss.

The tire pressure may well play a part in this, too.