Safer motorcycling part II : the variation of motorcyclists' accident risk with age, experience and motorcycle engine capacity.

In order to gain understanding of the factors giving rise to the disproportionate numbers of motorcycle accidents compared with other modes of travel, this paper summarizes two studies which use different types of data, but yield complementary results. These are: (I) the `STATS 19 Study' (Broughton, 1988, see IRRD 817339), based on police data from 1985-86 which included engine capacity, with detailed mileage data from the National Travel Survey (NTS): it dealt with the full range of injury accidents, but lacked riders' personal details such as experience and annual mileage, and (II) the `BSU Study' (Taylor and Lockwood, 1990, see IRRD 832455), carried out by the Behavioural Studies Unit of TRRL in 1988, using a questionnaire survey of 10,000 motorcyclists; this collected a wide range of personal and accident details, but the accidents tended to be minor and the data were self-reported. It is concluded that the main factors affecting the likelihood of a motorcycle being involved in an accident are age, length of riding experience and annual mileage. Engine capacity is only a factor in fatalities. For the covering abstract of the conference, see IRRD 840727.