If you have a 2" reciever on your quad, they make spare tire holders that fit into that reciever. I made my own, just copied the 110 doller unit, had some 2" sq tubing at the shop to fab it up. You need to carry a feont as a spare, front will fit rear, but rear will not fit front. Sport machines may be different then utility quads and probably dont have a reciever.

 

I have 2 comments about replacing ATV tires that have plenty of tread: they are supposed to have only 3-6 psi in them, and you can run them with no air at all for quite a ways without damage on the lighter quads. Now, an 800+ pound utility, not so much.