When I first bought my SV27 I ran it on 14 cells because I like to ride the edge, the motor fried within the first 2 runs. I sent it back and got a new one 3 weeks later. Then The new one started smoking on about the 4th run. It still runs but I don't think that stock motor likes 14 cells. I have since bought a new Feigao 12L from offshore which was recommended to me by Steve. I haven't installed it yet but it's supposed to be faster. I will see before the summer is over.