[scottyb]

The short answer is yes. The reason is because in upgraded speed controller will allow more amperage to flow from the battery pack to the motor. This amperage goes through the solenoid so solenoid must be rated high enough to handle the increased flow.
Typically 400 amp controllers require 200 amp solenoids. And larger controllers of 500 to 600 amps require 400 amp solenoids.
With this reason we combo package speed controllers and heavy-duty solenoids where the solenoid cost is greatly reduced.