Originally Posted by Dr_T

I made a little chart for deciding on my motor, depending on tire sizes, see below. Anything over 1700kv will result in a minimum of over 50 mph no-load gearing with >150 mm diameter tires because of the minimum 14T pinion and max 44T spur. You won't be able to gear a 2200kv on 6S for under 60 mph unless you get small tires.