Well basically you add or take off tyres on some buses at your own risk. One wheel flew off when we popped it and the bus shot up to a 45deg angle (front in air) and broke my friend's leg. We then tried the bus spawn at the next town over and if flipped over on its side crushing me. Was actually pretty funny but I imagine it could get annoying after a few times. This occured at stary sobor and novy sobor