by Lardog » Wed Jul 15, 2009 10:53 am
I'd normally go for about a 12 ounce tank for this size of engine. However, the Sportster engines seem to be extremely fuel-efficient, so you could probably use a 10 ounce, or even an 8 ounce tank for reduced size and weight.
Just FYI, my Hangar 9 Twist 60 (equipped with a .65 Sportster) has a 17 ounce fuel tank. I recently flew for 16 minutes and found I had used just a little less than 1/2 of the tank of fuel (about 8 ounces). Granted I wasn't running the engine hard (a lot of 1/3 throttle - a pretty tame flight for a Twist 60), but .5 ounce of fuel per minute of runtime on that size plane with a .65 engine is pretty impressive.
Larry