motorcyclists have the highest likelihood of being involved in a fatal crash of all vehicle passengers. given the multiple human factors that contribute to crash involvement, few personality models have been utilized to understand which riders are at a higher risk than others. the current study examines how several personality theories compare in predicting high-risk riding among north american motorcyclists. by utilizing personality theories such as the “big five” and “sensation seeking, and the novel application of “reinforcement sensitivity theory”, the relationship between personality and riding behaviour was assessed through online self-report questionnaires. the effect of each personality trait on speeding, stunts, and riding errors were compared within three hierarchical regression models, controlling for age, sex, years active riding, and aggression. among the strongest relationships observed were 1) sensation seeking’s positive association with speeding, 2) the reinforcement sensitivity theory’s the “behavioural inhibition system’s” positive relationship with rider errors, and 3) the big five’s “neuroticism” inverse association with stunts. these findings offer further support for the application of personality in determining individual differences in motorcycle crash risk and extend our understanding on how the reinforcement sensitivity theory contributes aversive health outcomes.