vehicle accidents, and accident involvement is significantly reduced by the use of motorcycle headlamps-on In daylight and the wearing of high visibility yellow, orange or bright red jackets. Fuel system leaks and spills are present in 62% of the motorcycle accidents in the post-crash phase. This represents an undue hazard for fire. The median pre-crash speed was 29.8 mph, and the median crash speed was 21.5 mph, and the one-in-a-thousand crash speed is approximately 86 mph- The typical motorcycle pre-crash lines-of-sight to the traffic hazard portray no contribution of the limits of peripheral vision; more than three fourths of all accident hazards are within 45° of either side of straight ahead. Conspicuity of the motorcycle is most critical for the frontal surfaces of the motorcycle and rider. Vehicle defects related to accident causation are rare and likely to be due to deficient or defective maintenance. Motorcycle riders between the ages of 16 and 24 are significantly Overrepresented in accidents; motorcycle riders between the ages of 30 and 50 are significantly underrepresented. Although the majority of the accident-involved motorcycle riders are male (96%), the female motorcycle riders are significantly overrepresented in the accident data. Craftsmen, laborers and students comprise most of the accident-involved motorcycle riders but the professionals, sales workers and craftsmen are underrepresented and the laborers, students and unemployed are overrepresented in the accidents. Motorcycle riders with previous recent traffic citations and accidents are overrepresented in the accident data. The motorcycle riders involved in accidents are essentially without training; 92% were self-taught or learned from family or friends. Motorcycle rider training experience reduces accident involvement and is related to reduced injuries in the event of accidents. More than half of the accident-involved motorcycle riders had less than 5 months experience on the accident motorcycle, although the total street riding experience was almost 3 years. Motorcycle riders with dirt bike experience are significantly underrepresented in the accident data. Lack of attention to the driving task is a common factor for the motorcyclist in an accident. Almost half of the fatal accidents show alcohol involvement. Motorcycle riders in these accidents showed significant collision avoidance problems. Most riders would overbrake and skid the rear wheel, and underbrake the front wheel greatly reducing collision avoidance deceleration. The ability to countersteer and swerve was essentially absent. The typical motorcycle accident allows the motorcyclist just less than 2 seconds to complete all collision avoidance action. Passenger