If there is a net torque, it's angular speed should change. But it appears that the angular speed is not changing (question says it's v/r, and doesn't mention that it's changing), it just turning with a constant speed. No net force doesn't mean no motion, it means no accelearion.
A torque is not separate from a force; it is impossible to exert atorque without exerting a force. Torque is a measure of how effective a given force is at
twisting or turning something. For something rotating about a fixed axis such as the bicycle wheel, a torque can
When stopping the bicycle wheel with two equal and opposite forces, the net applied force is zero and, thus, the wheel is in translational equilibrium; but the
net torque is not zero, so it is not in rotational equilibrium. Both forces tend to give the wheel the same sign of angular acceleration; they are both making the wheel slow down. The two torques are in fact equal, with the same sign.