Whether it be a desert singletrack or a loamy forest ribbons, the Schwalbe Racing Ralph tread pattern has become a common site. This is partly because of Schwalbe's semi-aggressive side knobs and fast-rolling, low-profile center lugs, but it's mostly due to its dual-compound rubber. And, now mid-wheelers are also able to enjoy the same winning combination with the new Racing Ralph 27. 5-inch Performance Tire. The Racing Ralph has become a tried and true favorite due to its fast-rolling tread pattern, and this newest revision only improves on the classic. The centerline of the tire features low, tightly spaced knobs knobs that provide enhance traction. And, true to its name, the tightly spaced knobs help the Racing Ralph roll blisteringly fast. The side knobs are wide and supportive, meaning that they'll bite hard to keep you from washing out when you're leaned over. But, tread patterns only tell part of the story. That's why Schwalbe uses its dual compound rubber, which places harder rubber down the centerline for a low rolling-resistance and an improved wear life. Additionally, the side knobs receive a softer rubber compound. So, in essence, you get the speed of a hard compound tire, mated to the cornering grip of a softer tire. This means that you don't have to sacrifice wear life for traction. The low-profile tread also has a U-Block shoulder tread. These tread blocks are angled at 20 degrees towards the outside of the tire. A small sipe doesn't quite divide the block, creating the 'U' shape. They work to counteract the lateral forces endured when cornering in order to maintain traction and to keep the bike stable. The Schwalbe Racing Ralph 27. 5 Performance Tire is available in the color Black and with a 2. 25-inch width.