Racebike Dynamics: The Dynamic Racebike State Plot

Riding a motorbike is characterized by permanent dynamics. In motorcycle racing the rider plays an important role in terms of its riding style -- the relative position of the rider in different riding situations on the racetrack. From an engineering point of view the riding style has a huge impact on the center of gravity position of the overall racebike and rider system. The different rider positions also have a strong impact on the aerodynamics of the overall racebike and rider system. Additional changes during a race or test day due to external influences or internal signs of wear and tear must be considered -- this applies to the rider as well as to components of the motorbike. This paper is based on the PhD thesis of Feichtinger and presents the dynamic racebike state plot as well as the derived quantity chi as representative characteristic for the dynamic of a racebike. This diagram was developed as a basis for all further analyses and investigations. It helps to identify and compare different motorbike variations and different rider types.