ORIGINAL: desertpig
There is no 40cc gas engine that is lighter than the DA50. I think the ZDZ 40 is the same weight, I know the others are heavier. In fact, the DA50 is lighter than most 25cc engines that is why most people use them. That, and they produce gobs of power.
IMO this plane seems like more of a glow plane converted to gas, kind of like the GP wagstaff. It will fly with gas, but a Moki or big OS is a better fit.
DP
the bme44 is lighter, by at least 7 ounces...