Depends on winding resistance, voltage , maximum (or minimum) acceptable current.
Minimum current limit will be set by starting torque.
Maximum current limit will be from one or more of the following: the capacity of the DC source; the thermal rating of the motor, in which case acceleration time also matters; mechanical strength of the motor / load / coupling / etc.
Resistors tend to be short-term rated. Time ratings are dependent on how fast your load accelerates, which in turn governs how fast the motor back EMF rises.
If you post some figures for max / min current and voltage, I will send you a worked example with your figures.
