Article by Paul Swift | Featured on BikeFit
This article is focused on road bike fitting and not bike sizing. Often these two descriptions become intertwined but they are completely different. With that said, fitting a road bicycle works best when you start with the right size bike; or at a minimum a bicycle that is close enough to your right size.
Sizing a road bicycle is not as complicated as you may have been led to believe, in part due to the reality that a good bike fit actually has little to do with the bicycle per se. Fitting a road bicycle comes down to the contact points (connection points) between the cyclist and their bicycle. These five connection points are: right and left foot, the pelvis and right and left hands. So even if your bike is not the correct “size,” as long as you get the connection points in the ideal place you can still achieve a good and comfortable bike fit.