Motorcycle Accident

Motorcyclist Accident Reconstruction Analysis in Illinois

Construction zone, Chicago, IL


Background: A motorcyclist attempted to change lanes in a construction zone, not realizing that one lane had been repaved but not the second, adjacent lane. The repaved lane was higher than the unpaved one, creating a step parallel to the direction of travel of the motorcycle. When the motorcyclist encountered the step, he crashed and was seriously injured.

What We Did: In reconstructing the accident, a scale model of the accident scene and was created for purposes of visualization to Jury members (see photo). A full-scale model of the uneven step and motorcycle tire was also constructed and tested to demonstrate the mechanics of the tire/pavement step interface and accident sequence. A third tabletop demonstrative aid/model was constructed to allow attorneys and Jurors to graphically understand the effect of a tire trying to climb the step (see photo).

Relevant Scientific Publications:

  • Metz, L. D., “Road Bicycle Dynamics in the Presence of Idealized Roadway Irregularities,” SAE Paper No. 2010-01-0053 [also in SAE SP-2267](2010).
  • Metz, L. D., “Behavior of a Motorcycle after an Encounter with a Road Irregularity Parallel to Its Direction of Travel,” SAE Paper No. 2006-01-1561 (2006).

Scale model of accident site.

Demonstrative aid.

Full-scale model and tire.

Motorcycle test rig hitch detail.

Truth can be an evasive fugitive.

St. Augustine, philosopher