Hi,
I own an elfi parkflyer. On my elfi the power seems to be much lower than it should have. I have a 400 motor i believe. The original one stopped working after 2nd flight. It got burned out or somthing. it lost almost all power and didnt always work. but now with the new motor it does fly, but still can barely climb at all. and it is hard to keep in air for while because of lack of power. It feels underpowered. I was told that the 400 motor is the original one on mine by my local hobby club. My battery pack is a 7 cell NiMH 8.4v 0.65 ah. it was puchased several years ago at hobby club. it holds a charge perfect. What do you think the problem is?

Battery? Motor? any input would be greatly apreciated. And i am using all very lightweight micro servos, sc, and rx. And also are there upgraded motors you can buy for the elfi?? thank you very much,
Alan Ryon