It depends who you are and what condition your in. Its all in the aerodynamics. It was a closed loop, elevation gain = 0, wind: head, both sides and tail. It would take 600 watts to go 25 mph on a conventional upright bike on the top bar, more with a mountain bike, I can cruse at that speed, < 200 watts.
https://www.facebook.com/darinandche...5227498015628/