The powered two-wheelers (PTWs; moped, motorcycles and scooters) have long been considered as a marginal population, but they developed significantly these last decades in most parts of the world, necessitating a new view concerning them. This is particularly the case in urban areas where their use has increased, notably linked to the possibility they offer to escape the problems of traffic congestion, which attracts an increasingly vast and varied population. In addition, PTWs can also be a good compromise to face in inner-city parking problems. As such, the motorized two wheelers are considered by certain authors as an essential contribution to the urban traffic of tomorrow. However, this view is currently contradicted by the poor level of safety linked to the integration of such vehicles within traffic. As a matter of fact, most epidemiological studies show the overall excess risk to which PTWs are confronted in the traffic system, this risk coming notably from the extreme vulnerability of PTW riders in case of a crash, and relying on some specific accident patterns. This negative effect must be neutralized for PTW to become a true urban mobility tool. The purpose of the present paper is to identify the causes and mechanisms of PTW traffic crashes occurred in town, notably comparing them with those produced in countryside areas. The data rely on a detailed analysis of a sample of 1308 accident police records. The results put emphasis on the difficulties met by PTW users on the road or in the street, and also the difficulties met by car drivers confronted to them. A better knowledge of the specificities and the mechanisms of PTW involvement in injury accidents is viewed as offering a potential improvement of their safety through an adapted urban infrastructure development.
accident configurations, human error, motorcycling, traffic safety, urban environment.
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