Originally Posted by Jimborama
Question: Why flip the stem upside down? Mine is already at a downward angle from back to front, is that not the most aero?
I think that this is one of those "case by case" instances. Meaning the bike may be more aero, but are 'you' more aero? This goes back to days when time-trialist used to think that if the bike was more aerodynamic then you must be fast. Now that philosophy has changed to state that the bike should be aerodynamic but it should also make the rider aerodynamic. Having an upside-down stem may put the rider in a more aero position as well as a more comfortable position. 'Cause lets face it, if you're not comfortable (position-wise) then you're not going to go fast. Also bike geometry and sizing can also play a part in the layout of the stem.