For completion of the type approval of two- or three-wheeled motor vehicles, and in particular of Directive 95/1/EC of the European Community, the Directorate General III (Industry) commissioned TNO Automotive (Netherlands) to perform a study to examine whether there is a relation between motorcycle accident occurrence and motorcycle engine power exceeding 74 kW. This report presents the results of a literature survey of existing studies, together with the factors that are likely to have a bearing on motorcycle accidents. Studies investigating the relation between performance properties and involvement of motorcyclists in accidents or the accidents risk used several different methods: (1) Studies searching for direct evidence of the following relationships: (a) Analysis of officially registered accidents, where accidents are weighted on the basis of the respective motorcycle population; (b) Questionnaires/interviews among a representative group of motorcyclists and accident-involved motorcyclists, where accidents are weighted on the basis of exposure to a collision (mostly distance travelled); and (c) combination of the two methods (both data sources); and (2) studies searching for indirect evidence of the relationships by investigating the effects of engine size/power restrictions for novice motorcyclists. The conclusion of this literature survey is that there is no scientific evidence that engine size is a major factor in motorcycle accidents; engine size does not emerge as a risk factor.
Samenvatting