Both recreational and competitive cycling such as strenuous ultra-cycling have grown in popularity over the last decades. Still, the underlying psychological predictors and their interplay with mental health are unknown. We therefore examined the psychological determinants and health outcomes related to the cycling ambitions of 2,331 international cyclists ranging from commuters via leisure to competitive ultra-cyclists. First, groupwise analysis showed that social and external motives, cycling-induced pain affinity, sensation seeking, benign masochism, low neuroticism, openness, conscientiousness and prior mental health problems most clearly differed between the types of cyclists, with values increasing by level of ambition (commuting vs. leisure vs. competitive). Yet, even within groups, we observed a strong variation of ambition. To capture these nuances, we created a path model with cycling ambition as a latent variable based on five indicators (e.g, frequency of cycling, following a training plan). Path analysis confirmed that social and external motives were important determinants of cycling ambition, partly mediating the effects of masochism and sensation seeking. Furthermore, while partly driven by prior mental health problems, cycling ambition positively predicted current mental health, suggesting that cycling may be a safe way to challenge oneself and potentially serves as a strategy to overcome psychopathological episodes. Longitudinal and qualitative research could follow up on some of the causal relationships proposed in the present model, particularly with regard to ambitious cycling functioning as a potentially unconscious self-therapeutic behavior.  Lay summary: Cycling is currently more popular than ever. To understand who cycles for which reason and with which consequences, we surveyed cyclists of various ambitions ranging from commuting via leisure to competitive ultra-cycling about their pain affinity, benign masochism, sensation seeking, motives for cycling, and mental and physical health.