There's not zero gyroscopic force, just negligible compared to the moment of inertia (with the tyre/ground interface as the axis of rotation) of the bike/rider

There's not zero gyroscopic force, just negligible compared to the moment of inertia (with the tyre/ground interface as the axis of rotation) of the bike/rider system. Furthermore you will notice a bicycle wheel rolling down the street often won't roll in a straight line (as it starts to tilt sideways, it will turn to bring the contact patch back underneath it), so even with just the wheel, the gyroscopic stabilization is insufficient on its own to keep it upright.