I am starting a new robotics project using some surplus motors I bought a while back. The motors have a 1/4" output shaft with a flat. For the life of me, I haven't been able to find a commercially available wheel that will easily attach to this size shaft. I like the banebots wheels, but they do not make a hub to fit a 1/4" shaft. I did find some nylon spacers locally that would bring the diameter up to 1/2". I could then use the Banebots hubs for 1/2" shafts, though I'd been limited to only a few wheel sizes. I was hoping to find something that would attach directly to the output shaft without adapters. Does anyone have any ideas? As far as size of wheel, I'm looking for something between 3 and 5 inches in diameter. The bot will live inside, if that matters. Thanks for your help.