An extensive quasiclassical trajectory study of the dynamics of the title reaction has been carried out on a six-dimensional, analytical potential energy surface, with the goal of understanding the role of the BO bond. For this purpose, trajectories for different hypothetical isotopes of the BO molecule have been calculated, for selected rovibrational levels of the reactants, at low and moderate collision energies. For all these cases, a clear departure from the BO bond spectator behaviour, as well as an unexpected role of hindered rotation normal modes at the transition state, is found.