But a couple of years back a guy called Brendonv built a kart which used shopping trolley castors as the steering supports. The way he did it was smart though and didnt involve the trolley wheel at all.
But yea, that way you want to do it is lethal and should only be used for slow speeds
Cool. I appreciate the feedback. I'm looking at this for VERY low speed (motorized couch). I think I'll do the steering differently based on all your feedback. Thanks again.
PS - here's the model I was going off of... http://motorizedcouch.pifflesquit.com/build.htm
If you're only doing low speeds & you use super heavy duty ones you may get away with it but you'd still have to come up with some kind of steering mechanism... could get very technical