[Ryland]

Most motors are geared down to allow for a smaller/cheaper motor, a hub motor has to be a low speed motor so that raises the cost, then you have to have two of them and two controllers, and two of alot of other parts so that doubles the cost.

Looking at one of these motors I notice that the top speed is around 850rpm, 155/80 R13 tires are around 900 rotations per mile, so under ideal conditions this motor could push you at just over 50mph? that is if the car is not to heavy, my 1,400 pound comuti-car has a 6,000 watt motor, these come in 3000W/4000W/5000W/6000W/8000W/10KW
The other promising looking motor is a 5,000 watt motor with a top speed of 800rpm and a "12" car rim" not what most people would want for an electric vehicle, but it could work.
Alot of those companies will ship you a "sample" altho the shipping will almost kill you, we had a box that was maybe 2 cubic feet shipped with some cabinet door samples, shipping was well over $300 plus the cost of the samples.

Hub motors work great for bicycles because they make it simple, I think they would work well for a small electric motorcycle as well, maybe two of them for a motorcycle.