It is not optimal, that is for sure. I have done it on a couple of occasions when the demands of a flat tire necessitated it. Just know it will probably be noisier, handle much worse and should be avoided in rain or snow. Keep it at slower speeds as well. Think of it as having your space saver spare on there and drive accordingly slow. And get the tire replaced ASAP so you don't have to drive around like that.What would happen to a directional tire if you were to run it backwards? By backwards I mean running it on the other side of the car. I have an extra tire and would like to use it as a spare for short periods of time.