At the 2006 UCI Track Cycling World Championships, Bos won the keirin and completed a career triple, having been world champion in the sprint, kilo and keirin. He won the keirin after accelerating with two laps to go, winning by a wide margin and able to raise his hands and salute the crowd as he passed the finish line. His French rival, and bronze medal winner, Arnaud Tournant, said Bos' performance was "the best I've seen in a very long time."