  Automotive traffic is a classical example of a complex system, being the
simplest case the homogeneous traffic where all vehicles are of the same kind,
and using different means of transportation increases complexity due to
different driving rules and interactions between each vehicle type. In
particular, when motorcyclists drive in between the lanes of stopped or
slow-moving vehicles. This later driving mode is a Venezuelan pervasive
practice of mobilization that clearly jeopardizes road safety. We developed a
minimalist agent-based model to analyze the interaction of road users with and
without motorcyclists on the way. The presence of motorcyclists dwindles
significantly the frequency of lane changes of motorists while increasing their
frequency of acceleration-deceleration maneuvers, without significantly
affecting their average speed. That is, motorcyclist "corralled" motorists in
their lanes limiting their ability to maneuver and increasing their
acceleration noise. Comparison of the simulations with real traffic videos
shows good agreement between model and observation. The implications of these
results regarding road safety concerns about the interaction between motorists
and motorcyclists are discussed.
