I bought my first cobra s4 from mpr, and it came with street tires. I bought a second quad from PBU, the stock custom quad, and that came with knobby tires for $260 + shipping. It looks just like my s4 except for the front suspension. My s4 tires are going bald in the back, but it still rips through it. It's been a lot of fun with the snow and ice we've been getting