I agree with Matt in regard the soft mount. If you are planing to build a 2 meter plane under 11 lbs you better install one. I tried around 10 years ago to hard mount a gas engine (ZDZ 40) in a very light airframe and almost lost the plane due to aileron flutter. After installing a soft mount the problem was resolved. I noticed that battery consumption was reduced about 40% because the servos were working less against vibration.