Hi, i would love to get any help with a project i'm working on. I'm building Electric Rollerblades. Each Rollerblade would have two wheels - one at the front of the shoe, and one at the back (with the motor attached to it). I Was wondering what would be the best proportion between the wheels size and the shoe length? Is it depends on the weight of the person using? The type of the motor? Or maybe the speed? Any ideas would be great! thank you!