the UCI has their own rules for bikes, which extend far beyond just banning recumbents. They just reiterated their ban on saddles that aren't level, for example. If someone wants to compete with the UCI for holding records for recumbents, they can feel free. I'm sure Mexico City will rent them track time. Recumbent records hold their own problems though, the timed mile record is over 80mph. They'd probably have to hold the record attempts on a car track somewhere.