If you have to add the weight you my as well use NiMH battery's they are heavy and last 2-3 time's as long as regular battery's...the ones I use are 4.8v@2000mAh and weigh a porky 135 grams or 4.8oz's run 2 of them and you can charge then on Sunday and fly all week....these are what I'm installing in mine.....but I don't need as much weight because I'm running a YS63S.....you can see them @ tower hobby's ...part # HCAM6320........JW