Cheers Les, i think you have hit the nail on the head, i was trying to run this of eight cell AA 1600 zagi batteries but they obviously cant deliver enough current. When i run it off Sanyo 2400 subc 7 cells it goes like crazy. I have it earmarked for a Zagi so i am guessing i will need to go and bouy some seven cell 4/5 subc 1300mah packs. Can anyone recommend a prop for this motor, i currently have a 5x5 on it but havnt a clue what amps thrust etc it is pulling. I am new to all this and any help would be appreciated