Roulston was selected for the New Zealand team to compete at the 2008 World Track Championships in Manchester where he narrowly missed medals in the 4000 m individual pursuit (4th) and Team Pursuit (4th) as well as finishing 9th in the Madison with Greg Henderson. Having performed so strongly in Manchester, he was selected for the Beijing Olympics, where he focused on improving his 4th placed pursuit rides. Former New Zealand track coach Ron Cheatley suggested his best bet will be to drop the Madison and focus on the complementary pursuit events in much the same fashion as Kiwi pursuit rider Sarah Ulmer. Ulmer quit road racing and focused solely on her pursuit preparation before the 2004 Athens Olympics where she went on to smash the world record and take the gold medal in the women's 3000 m individual pursuit.