The choices are limited. It took me 13 levels and a thousand miles just to unlock the Zwift Aero Bike (and the color drag goes from lame to lamest).
Level 17 unlocks a Parlee. Level 20 gets you a Madone.
Today, however, I was riding with another rider on an S-Works. A bike not listed. How is that possible?
Are there other bikes you can unlock with promo codes that I am currently unaware of?