Schwing!


But seriously, if you think a 55cm bike is appropriate for you and your current bike is a 51, a stem isn't going to help much. The frame is the foundation of your bike. Stems, saddle adjustment, seat posts, and crank arm lengths simply fine tune that foundation.

Sounds like you should look at your frame (or an entirely new bike) before spending good money on a stem.

Bikes are like shoes in that doesn't matter how nice or how free they are, if they don't fit you won't use them.