Do not run a prop larger than 42mm in diameter with the 7XL, at least not at first. An x438 or x440 would be good places to start. I have run 40mm props on my MM and it runs well. I would not run a carbon prop since your rpm will be very high with this setup and the blades will distort. You can pull a lot of amps with your setup, what is the C rating of the cells? That is really the limiting factor of your setup, the ESC will handle more than the cells will.

My MM runs well with the CG at 9.5". Some others prefer closer to 8.75". Like Saleen7 stated, it can depend on your setup, speed, prop size and depth, etc.





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