[shawmutt]

What's missing here is the bell curve displaying gas economy. For instance, I know that my motorcycle gets 55+ mpg when riding easy at 60mph, but dives down to 45+ mpg when riding hard at 70 mph. Does anyone know a source that displays what the best speed is for the majority of cars to get the best gas mileage? The speed limits just seem like arbitrary numbers to me, 55 in New York, 65 in PA and MD, 70 in WV...