I am finishing my meanie and have a couple of questions.
First , I am using a 7XL motor ,hydra 240 SC, 4s 4000"s wired parallel.
I really need to know where the best balance point is on the hull ?
And is the 642 a good prop to start out with?

Thanks
Tim

the balance point is different with every boat, but there usually somewhere between 25-35% of the boats length from the transom...with some cats the balance point is around the middle of the space between the first step and the second step. i would suggest an 8XL instead of a 7...may have less rpms, but you will be pulling less amps and it will have a little more tourque, so you can run a larger prop....i cant really tell you wat prop will work, but i would suggest getting carbon props (can be found at OSE) around the size you think will work best...(i.e. between 40mm-48mm) and test out each one....try the smallest first...if the motor is cool or only slightly warm, you can prop up...keep on using a bigger prop until the motor starts getting warm...once you find the right one, buy a metal version all balanced and sharpened up....this is a good way to find the right prop without spending a lot of money on a buch of metal props...

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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I think it is 20, at least one of the batteries says that. they are sold by fine design under the name of firefox pro matched racing.