[sleebus.jones]

I aim for a motor RPM of 35,000. (I think this was BrianG's suggestion) First, I decide how many cells I want to run. Divide 35,000 by volts of your pack and *pow* there's your KV value. Find an XL motor that matches and you're good to go.

I've found that the motor you get when you follow the above formula is very tolerant of gearing. I'm running 5S on my hyper7 with a 10XL, it's geared 13/46 has tons of acceleration and refuses to get more than barely warm. I think I'd have to get to 15/46 to get any real heating to start, but that'd be more speed than is usable on the track.

Your choice of the 7XL fits right in with this.

As for which motor to pick from the choices you listed, well...they're going to be pretty much the same. You see, you're dealing with a set amount of power...your battery. Without changing that, going outside of the "normal setup" really isn't going to bring you much benefit. To really make a change, you have to change the power avalible to the system, that is add a cell. Then dropping the KV will make some sense.

The bottom line is that if you drop the KV and change the gearing to bring the speed back up, the same amount of work is being done, so I wouldn't expect much change.

Either that or I'm all wet. :)