Challenge creates handmade tubular and open tubular (clincher) tires using an artisan process that allows the rubber to retain its natural properties. By avoiding the industry-standard vulcanization process, which requires extremely high heat, we provide tires with the superior grip, performance and comfort required by demanding professional athletes and everyday riders. Continuous research in sophisticated raw materials and production processes make us unique. Challenge offers top-end silk and cotton casings with the highest thread count possible, plus puncture protection and advanced natural rubber compounds for suppleness, safety and strength. Demanding riders who strive to excel choose Challenge.