Since 1969 there has been a spectacular increase in the popularity of the bicycle. As a result, not only have bicycle/ motor vehicle collisions been on the rise, but major shifts have occurred in the age distribution of victims of these collisions. The greatest increase in involvement rate is among bicyclists between 15 and 34 years of age, while that of the 5-14 year age group is decreasing.

This paper presents age-specific critical behaviors of the bicyclists as a basis for countermeasure development with regard to age. Countermeasure activity that addresses these critical behaviors exists only to a limited extent, particularly in the teenage and young adult area.

City accident information was collected as part of the American Automobile Association's Special Survey on Bicycling and Bicycle Accident Records for 1974. Some 11 categories are used to identify actions of the bicyclist prior to a collision involving a motor vehicle