Challenge once licensed post-Pirelli years Clement Tire, the famed 'cross tire maker. In doing so it picked up several key tread design cue from Clement. As a result, one of the most closely duplicated cyclocross tire treads of all time is that worn by the Grifo. The best all-around cyclocross tire ever created excels in wet or dry, soft packed, rocky and root-infested courses, grass, and more. The Grifo features fast rolling, biting knobs and a center section that offers excellent pedaling and braking traction. Challenge H-TLR tires meet the new ETRTO and ISO standard and are hookless compatible, and can be used with a tube or as tubeless with hooked bead rims as well. Handmade TLR tires from Challenge are best combined with the Challenge’s Smart Tubeless Sealant, which protects the natural properties of its components for a longer lasting performing tire, while further enhancing puncture protection and air tightness.

Challenge builds the Grifo Pro Series TLR tire with it's 300 tpi SuperPoly casing, a lightweight fine weave of soft polyester fibers that is both supple and resilient- perfect for cross racing. You get added protection from the PPS puncture strip, which is constructed like a fabric, with properties that match the casing for excellent ride consistency. The components react, responds and roll faster as a result of this combination- which is the ideal counterpart to the Grifo's loose-to-mixed surface purpose. It gives that little bit of speed advantage combination that comes from lower rolling resistance and rider confidence.