TRUE OR FALSE: Riding with a standard bottle (or two) on the frame is an aerodynamic disaster
You might have guessed, this is TRUE. Round bottles are a big penalty on most bike frames because they massively increases turbulence around the frame tubes. Cylinders are one of our enemies in aerodynamics.
Our pro tips?
If possible when racing a triathlon, use an aero-shaped frame bottle for storing gels, and a cockpit-mounted hydration system for your fluid intake. Alternatively, mount round bottles behind the saddle (for non-UCI racing) where they can be aerodynamically neutral.
If you are a UCI road cyclist, consider aero bottles for short races. In the sprint, make sure you have removed the bottles before the sprint phase, not for the weight effect (which is tiny) but for the aerodynamics!