The tank holds 3.7 gallons of fuel. My highest is 165 miles on a tank. That´s roughly 45 mpg. And that was to bone dry. I wanted to see how far I could go past the safety gauge that starts flashing on the display, which I got to 23 miles. That was all highway in 85-95 degree weather. I averaged anywhere between 75 to 85 mph,a couple of times reaching 95, but very briefly. That was shortly after my 600 mile break in period. In the city my lowest is 138 miles to the tank. That equates to about 37 mpg. I was in Los Angeles and it was stop and go, steep grade terrain.