I did use the same fuel I do that with all the engines I get. The break in fuel was just the amount I used to break it in wich was probably about 2/3 of a gallon maybe more. The engines above are the ones I'm interested in plus the ninja I think it has a balanced crankshaft the picco and the novarossi I have heard are different but I don't really know much about that maybe the axial failed because of this as there did not seem to be a counter balance weight like my aero engines. Any info would be great.