![Challenge Shows New Grifo Clincher and Gravel Grinder Tire at NAHBS 2014 - Cyclocross Magazine - Cyclocross and Gravel News, Races, Bikes, Media Challenge Shows New Grifo Clincher and Gravel Grinder Tire at NAHBS 2014 - Cyclocross Magazine - Cyclocross and Gravel News, Races, Bikes, Media](https://www.cxmagazine.com/wp-content/uploads/2014/03/challenge0.jpg)
Challenge Shows New Grifo Clincher and Gravel Grinder Tire at NAHBS 2014 - Cyclocross Magazine - Cyclocross and Gravel News, Races, Bikes, Media
![Challenge Grifo Cross Open Tubular Tire (Clincher) (Black/Brown, 33-mm) : Bike Tires : Sports & Outdoors - Amazon.com Challenge Grifo Cross Open Tubular Tire (Clincher) (Black/Brown, 33-mm) : Bike Tires : Sports & Outdoors - Amazon.com](https://images-na.ssl-images-amazon.com/images/I/41Qh3THco0L._SR600%2C315_PIWhiteStrip%2CBottomLeft%2C0%2C35_PIStarRatingFOUR%2CBottomLeft%2C360%2C-6_SR600%2C315_ZA16%2C445%2C290%2C400%2C400%2CAmazonEmberBold%2C12%2C4%2C0%2C0%2C5_SCLZZZZZZZ_FMpng_BG255%2C255%2C255.jpg)
Challenge Grifo Cross Open Tubular Tire (Clincher) (Black/Brown, 33-mm) : Bike Tires : Sports & Outdoors - Amazon.com
![Challenge Shows New Grifo Clincher and Gravel Grinder Tire at NAHBS 2014 - Cyclocross Magazine - Cyclocross and Gravel News, Races, Bikes, Media Challenge Shows New Grifo Clincher and Gravel Grinder Tire at NAHBS 2014 - Cyclocross Magazine - Cyclocross and Gravel News, Races, Bikes, Media](https://www.cxmagazine.com/wp-content/uploads/2014/03/0challengegravel.jpg)
Challenge Shows New Grifo Clincher and Gravel Grinder Tire at NAHBS 2014 - Cyclocross Magazine - Cyclocross and Gravel News, Races, Bikes, Media
![Challenge Unveils Grifo Race Clincher, Hints at New Gravel and Fat Bike Tires, Colors - Cyclocross Magazine - Cyclocross and Gravel News, Races, Bikes, Media Challenge Unveils Grifo Race Clincher, Hints at New Gravel and Fat Bike Tires, Colors - Cyclocross Magazine - Cyclocross and Gravel News, Races, Bikes, Media](https://www.cxmagazine.com/wp-content/uploads/2014/03/challenge-cyclocross-gravel-tires-cxmagazine-img_9870-e_1.jpg)
Challenge Unveils Grifo Race Clincher, Hints at New Gravel and Fat Bike Tires, Colors - Cyclocross Magazine - Cyclocross and Gravel News, Races, Bikes, Media
![Amazon.com : Challenge Grifo Cross Open Tubular Tire (Clincher) (Black/Brown, 33-mm) : Bike Tires : Sports & Outdoors Amazon.com : Challenge Grifo Cross Open Tubular Tire (Clincher) (Black/Brown, 33-mm) : Bike Tires : Sports & Outdoors](https://m.media-amazon.com/images/I/71ZMB3c-GIL._AC_SX425_.jpg)