When we're in the market for a rear tire on our cross-country race machines we immediately turn to the Schwalbe Thunder Burt Addix Evolution 29in Tire. This hyper fast-rolling tire is a speedy addition to our ride with plenty of contact points and aggressive side knobs. We're rolling up to speed and getting through this 2 hour XC race in just an hour and a half with this quicker than quick rubber on our rides.