The effect of engine spin direction on the dynamics of powered two wheelers is investigated in terms of steady-state points (equilibria), vibration modes (stability), manoeuvre time (performance/manoeuvrability) and handling. The goal is to assess and quantify the advantage sometimes claimed for the \u2018counter-rotating\u2019 engine configuration, where the engine spins in the opposite direction with respect to wheels, against the \u2018conventional\u2019 configuration, where the engine spins in the same direction of wheels
