Official casualty statistics show that young motorcyclists are more likely than older motorcyclists to be killed or seriously injured on the roads. We address two main issues: might the statistics be attributable to inexperience rather than youth; and might accidents be associated with particular patterns of behaviour which may themselves be predictable from riders' beliefs? From a national prospective survey of over 4000 riders in the U.K., the data showed that youth played a much greater role than inexperience, and that accidents were associated with a particular pattern of behaviour, namely a willingness to break the law and violate the rules of safe riding, which was predictable from the riders' beliefs measured 12 months earlier. The implications of the findings are discussed both for theory and for policy and practice, and particular emphasis is placed on suggestions for modifying training courses.