On small tracks it's around 40, sometimes a bit higher. The big tracks, now usually 333 meters are where the 60+ speeds happen.
Pros can get over 40 now with no drafting or very little, but only briefly. The world record for 1KM (roughly 1/3 of a mile) is 1 minute .082 seconds. Or an average around 37mph. But it's from a standing start, so the actual speed is somewhere over 40. Shorter distances can be done at maybe 45 or so.
The motorpacing is faster, or just as fast over a longer distance. While keeping up with the motorcycle is important because the motorbike is shielding the rider from the wind, There's usually some communication. Done purely by shouting in the old days. (Yeah, imagine biking at 40mph and still being able to shout to the driver to speed up
) Getting out of the draft is a rough ride, coming out of rather still air into what's essentially a 40+ headwind. Bad enough to cause a crash.
At those speeds the draft doesn't really pull you along.
The motorpacing like Rompelberg did is a whole different thing. The gearing is so hard they're towed to around 60, then released. (The two or three most recent only) The previous record holder is one of my favorite cyclists. His record was 152, and at somewhere over 140 he ran into an odd aerodynamic effect where the vortex from the turbulent area around the car caused a serious tailwind inside the draft area. That ended up slamming him into the back of the car a few times. But he still had to keep pedaling or drop out into the 140+ air around him. It stopped around 150.
Only a handful of people have managed over 100.
Alf Letourner 108 in 1941 And on wooden rims too.
Jose Meiffret 125 in 1962
Alan Abbott 138 in 1973 First one done at Bonneville salt flats
John Howard 152 in 1985 (in 1984 he tried on a stretch of highway in Mexico and reached 124 AND had a flat tire on one run at 100+)
Fred Rompelberg
Meiffret constantly increased his record during 51 and 61-2 And Rompelberg ran over 100 in the 80's before crashing then came back in the 90's and gradually improved until he had the record.
Aside from downhill mountain bikers I don't know of any others over 100. Meiffret was the only one that continued after he had the record. Including all the previous record holders back to mile a minute Murphy in 1899.
I've had my 80's motorpacing bike over 30 unpaced, and that's being out of shape and overweight. It really wants to go fast.
Someday I'll convince one of my friends to let me try it behind a minivan. There's only a couple I'd trust to drive, and neither has agreed yet. They think it's too crazy.
One of the things I like about the bikes is being able to take them out and ride them fast. I can't imagine taking either of the game used bats I have to the batting cage.
Steve B