ORIGINAL: mrluke
its all stock GWS. It all came in a flight pack with a gws 7.2/270 batt the batt i tried today is the batt I used in my Corsair its a thunder power 2 pack 7.4 1320
The Thunder Power 2-cell pack of 1320mAH Li-POLY are pretty heavy and subsequently the model will struggle with this weight and the propeller RPMs will not have enough power to perhaps make this model fly sufficiently with this weight.
I use some older (but, effective) 2-Cell, 1025mAH, Li-POLYs that keeps the model light enough.
Another possibility is perhaps the motor is just at the end of it's Life Time and the motor is just not producing those RPMs as when new.
Carlos