I just ordered a set of Specialized 20"x2" Rhythm Lite Sport tires for my Hooligan. The Rhythm Lites have a slightly knobby, raised center ridge for pavement, but medium sized side knobbies for the dirt. For me, the stock tires (20"x1.5" Kendas) don't have enough contact with the road - On any given day I can be on a dirt road to a mountain bike trail and back to the pavement, and the skinnier Kendas just can't handle that kind of variability. I was thinking about getting the full out knobbies, but I ride more than just trails, and I hate the way knobbies thrum on the pavement. I was initially concerned about the extra weight and rolling resistance of a larger tire, but in such a small wheels those aren't major issues. If anything, I could use a little more resistance when peddling - sometimes the Hooligan is just TOO EASY to peddle for the workouts I like to get when I ride it. It is so much easier to flick around the pedals on my Hooligan than my other bikes that I have to ride farther to to get the same cardio benefit. I had to put on a pair of Egg Beaters to keep my feet from flying off the pedals, but other than that this bike doesn't require any major upgrades - it's fun right out of the box.