You can find information regarding the reduction of speed while using a spare tire on
A. the side of the spare tire
Step-by-step explanation:
The spare tire is a safety measure and is not comparable to a real tire in terms of performance, durability or strength. The spare tire is only to give a window of usage for the vehicle to reach a place where the main tire can be replaced.
So the tire is not good for high speed driving and will have to be used with certain precautions. Usually these precautions vary according to the ones that are getting used so it is prudent to check on the side of the spare which has the information that is required.