In this study the rail wear influence in terms of safety of rail vehicle motion is assessed. The profile measurements for the nominal rail head and for the slightly worn and heavily worn rail heads were performed. Then, these measured real values were entered into a computer program designed to study the motion (dynamics) of rail vehicles. The studied model of passenger vehicle moved in simulations along a track consisting of straight and curved sections with transition curve between them at two velocities. After obtaining the simulation results, they were compared for different stages of the rail wear process based on profile measurement results and the suitability of the track was assessed, too. The aim of present paper was to show that extension of the traditional approach with the simulation studies of vehicle motion and dynamics leads to different and much more precise information about the need of the rails displacement. The proposed idea and approach in the current work is original and not used in practice by the track infrastructure operators.