Originally Posted by
ruudlaff
My assumption with this is that the rider calls out however fast they feel they can hold on to the derny?
Sort of. They definitely communicate, when they can. But it's not just a matter of how fast a rider can go - it also comes down to how good a derny driver is: when they add speed to effect a pass and how they time that at 45mph with X number of laps to go. A derny driver might just say "stay with me!" and essentially make his own move.