I know this is an older thread but I wanted to add my two cents. If you ever have a stubborn stiff walled tire or even an ancient used one that is a little hard (car or bike), try tire dressing as a lube (Armorall, Tire Wet, etc) It works great and has the added bonus of not drying out quickly if you have to work outside on a hot sunny day. Dishsoap and water usually work okay, but I've found on a hot day you have to reapply it so often on a stubborn tire that you end up with a buttload of water in the tire. If you don't get all the water out it's almost impossible to balance the tire correctly (it'll drive you nuts) and of course the water can cause corrosion of the rim. Just be careful if you're making descent horsepower because, even though its never happened to me, I've always wondered if it may be possible to shift the position of the tire on the rim until the dressing looses it slipperiness, if you hook up hard on a launch. Also if you end up with dressing on the tread face, go real easy on the throttle and corners until you scrub it off.