10/10/2012:
I Ran the 25 AME BB with muffler, 10X6 APC propeller, 5/29 all castor fuel, 4 oz. Tank on my test stand. Recorded 11 minutes running steady @ 10,200 RPM.
Since I regard this engine as a superb potential replacement for my venerable Fox 35 CL engine, I figured that for a typical 7 minutes flight it will require only 2-1/2 Oz. tank. This could lead to a saving of possibly 3 - 5 Oz. if the engine will be equipped with a Tongue Muffler.