Reducing risky behaviors and traffic violations is crucial for preventing road trauma among private and commercial motorcyclists. While legal interventions such as road rules and police enforcement have been somewhat effective, there is a gap in understanding how motorcyclists perceive these deterrents and the psycho-social factors influencing their effectiveness. This research aims to explore the interplay between motorcyclists’ psycho-social predispositions and their responses to legal interventions. It also compares two distinct groups of riders - private and commercial motorcyclists - within the urban environment of Da Nang, Vietnam, providing a nuanced consideration of the influence of work-related impacts on risky behavior, which can enable targeted interventions. We propose a theoretical model integrating the Theory of Planned Behavior and Deterrence Theory to analyze how psycho-social and punitive factors influence riders’ traffic violations. A total of 423 delivery riders and 411 private riders in Da Nang participated in the study. The results show that attitude, perceived behavioral control, and perceptions of deterrence significantly impact riders’ intentions to engage in risky behaviors, with delivery riders being particularly responsive to law enforcement and penalties. To enhance policy effectiveness, interventions should employ tailored enforcement strategies that account for the unique motivations and perceptions of each rider group. For example, increasing the visibility and consistency of law enforcement could be particularly impactful for delivery riders, who are more sensitive to immediate deterrents. Policy adjustments should also focus on reshaping riders’ attitudes toward safety and adjusting their perceived control over riding situations. By tailoring interventions to effectively influence each group's behavior, we can ultimately reduce traffic incidents.

In recent years, the growth of motorcycle-based ride-hailing and delivery services has led to an increase in traffic crashes involving these riders. Previous studies have indicated that the behavior of ride-hailing and delivery riders is influenced by work demands and individual characteristics. However, the extent to which risky riding behaviors depend on the type of riding and the interaction between road traffic context and risky behaviors remains unclear. Addressing these gaps, this study investigates factors influencing risky behaviors among motorcycle riders in Hanoi, Vietnam. By examining various rider traits (such as rider type, gender, and age) and aspects of the road traffic environment (such as police presence, number of road lanes, and weather), we aim to understand their contribution to risky riding behaviors. Through the observation of 9164 motorcycle riders (i.e., delivery, ride-hailing, and private motorcycle riders) at 31 intersections and decision tree analysis, the study underscores the significant impact of rider type on risky behaviors. Key findings include a higher tendency for both delivery riders and ride-hailing riders to run red lights, neglect to use turn signals, and the notable distraction of mobile phone use. Additionally, private riders are found to show a higher incidence of not wearing helmets even in locations with a police presence. These findings highlight the critical need for strategies to enhance road safety for all motorcycle riders. However, it is essential to recognize that the reasons behind risky behavior vary across different groups of motorcycle riders, from private to commercial riders. Therefore, we need more targeted strategies that address the specific factors influencing each group to effectively improve road safety for all.