317mm * π * 333rpm = 6.00 m/s = 21.5 km/hand max power with torque/speed:
17.68 Nm / .158m = 112 N = 11.4 kgfAt which point it'd be drawing something like 20A, so to make it useful the power pack would have to be biggish. Might make a nice "first EV" though ... and you could always carry it in the boot as a spare!
317mm * π * 263rpm = 4.36 m/s = 15.7 km/h
It's interesting to think about range: at max speed (21.5 km/h) it's drawing about 5A, so assuming a 10Ah supply would go about 43km. At max torque, it's drawing about 20A and only going 15 km/h, so its 10Ah supply would go about 7.5 km ... about 1/6 as far!
This 10Ah NiMH battery pack has 30 D-cells and is 162 * 97 * 45 mm and 5kg.
(If I put skateboard trucks or similar on the front, it'd technically be a leaning tadpole trike :-). Yes, I know there's already plenty of these kind of things on the market ... but it'd still suck less than a Segway.)