speeds = np.linspace(0.0, 10.0, num=200)

ax = model.plot_eigenvalue_parts(v=speeds,
                                 colors=['C0', 'C0', 'C1', 'C2'],
                                 show_stable_regions=False,
                                 hide_zeros=True)
ax.set_ylim((-10.0, 10.0))