This is where it is good airmanship to be aware of the expected ground speed at VR as a double check.
How would you propose to observe that groundspeed?
For me, I scan the ASI along with temps and centreline until I am crosseyed by which time it must be time to haul back. Non standard calls during the roll are extremely difficult for just this reason.
By the way, tell me about these throttles? What sort of jet engine uses carburettors?
