There is no spike if the diode is intact, and the spike is at the collector of the transistor anyway,
its only when the spike is present and destroys the transistor that it will get to the power rail.
The standard way to protect a voltage rail from spikes is with a crow-bar or clamp circuit, typically driving
an SCR to turn on and low the fuse, or a clamp using a zener and transistor to conduct away the spike
but without permanent effect.
There is another issue with spikes causing interference, this will be more important the
higher the motor power (voltage and current), and shielding and EMI prevention measures
may become important.