The motorcycle racer heads to Colorado where he hopes to win one of America's oldest races - the Pikes Peak International Hill Climb. In this annual contest, known as the Race to the Clouds, riders compete against the clock on a gruelling mountainside track that finishes more than 13,000ft above sea level. To learn the skills required in hill-climb events, Guy visits the birthplace of the sport - Shelsley Walsh in Worcestershire. Racing up the course in an F1-style car, he realises sheer horsepower and driving precision are vital, but he must also take a high-altitude fitness test in a hypoxic chamber to prepare for the challenge ahead