I normally use 2200-2400 rpm as my cruising speed. For fuel consumption, I assume that it uses about 1/3rd gallon per hour. That level is higher than actual, so it gives a cushion. Unfortunately, I don't have a good way to measure the fuel tank either. Mine has an approx. 6 inch inspection port on the top that's attached with about 8 screws. To check fuel, I usually just undo the screw and look in.
