I'm a points guy, I'd say I probably tap out about 100RPM, probably only max out about 120-130RPM in a sprint (55-58km/h), pushing generally either 96 or 98 inches. While Kayce is right to some extent, you do find large segments of races that do hang together, where you're sitting on a pretty quick speed, with accelerations on the sprint laps obviously.
I think the standard used to be to go shorter than road setup, and I think this is still very common amongst the guys doing lots of sprint events, but for a lot of mass start riders (ex Kierin) I've seen the lengths creep up over the past 10 years. Same with pursuit, where I'm seeing guys synch with their TT type setups, which are a bit longer (I ride 180mm on my TT setup). If I ever get round to a season focusing on pursuit (rather than a side line, I'll go longer than 175).
My own stats I'm 6'2", 57.5 effective TT (58mm on my road bikes), about the quickest I ride is in scratch races, where I'll hit around 62-63km/h in the sprint. It's one of those things where over time you'll find out what works best for you and what doesn't same with pretty much every other setup aspect on a bike.
I started track racing after a long road career on 170's. While now I'd prefer not to ride that short, I don't think they held me back any.