Investigations into motorcycle accidents with motorcycle carrying not only driver but also pillion passenger have so far been unknown. However, qualitative observations of accidents indicate that, owing to the mutual influencing of the motorcycle riders, this accident type follows a different sequence from one in which the motorcycle is carrying only a driver.

In experimental accident simulations, motorcycles, carrying two riders, impacted laterally at 90 degrees and diagonally (45 degrees) against stationary passenger cars in the speed range between 50 and 60 km/h.

There is a description of the essential differences in the motion and impact characteristics as well as in head and body postures between driver-only and driver-plus-passenger accidents. Derived from this are safety-related considerations regarding design measures on the motorcycle in order to optimize the motion paths of the riders.

Bases for the reconstruction of this accident type are elaborated.

With regard to the safety of a passenger car and its occupants in the event of motorcycle impacts, the structure of the side assembly and the testing of its strength are discussed.