Statistical data from field accident research evidently show high relevance for a motorcycle impact investigation. Retrospective accident research requires detailed information about motorcycle impact kinematics and rider's trajectories.This study documents results of impact tests with instrumented dummy on different motorcycles, simulating intersection and frontal collisions, the most hazardous collision types. Analysis is focussed on dummy kinematics, in regard to interaction with motorcycle (fuel tank, handle bar) and head impact on the car body.High head impact load was observed when structural car body parts were hit. Corresponding lab tests with different helmet sizes were conducted, which showed low efficiency of current production energy absorbing (EA) material. Helmet protection potential is too low, EA material too strong. Thickness-efficiency (TEFF), which is defined herein, is low. Alternative material with higher TEFF showed much better results.