Without going into sticky biomechanical issues, we can start from the simple consideration that efficient pedalling requires the rider to be positioned properly on the bike.
Once you have chosen the type of frame, as well as its correct size, it will therefore be necessary to make a few small adjustments on the bike (seat height and saddle setback, stem, etc. …) to find a position which provides the right balance between comfort and performance.
Of course, the physical characteristics of individuals, along the entire length of the thigh-bone and arms, are decisive for the final result.
In the case of a “classic” position, there is a general empirical assessment that always enables us to establish, with great precision, the exact position in the saddle.
Quite simply, this consists in making sure the front part of the kneecap is positioned “straight down” with the metatarsus when the pedal crank is horizontal.
This is the reference condition from which to start setting the other parameters correctly.
In other words, the upper part of the cyclist’s body is, so to speak, subordinate to the lower part: what conditions the seat is the leg that pedals, not vice versa.
In all this, a fundamental variable for finding the right position and a more rounded pedal stroke is represented by saddle adjustment.
If the movement of the saddle back or forth is to be established in relation to what was said above regarding the angle of the knee, we at Colnago agree that it is better not to exaggerate with the height, inasmuch as a lower saddle allows a “fluid” pedal thrust and pick up cycle, with more continuous performance over time. When the saddle is too high, the thrust phase is exalted, but the pedal stroke becomes to some extent elliptical and less efficient in the long run.
During a performance of several hours, it is in fact essential to adopt a pedalling technique that allows moments of recovery, and wider and more complete muscle involvement.
Mounting the saddle too high is instead a very common mistake among enthusiasts, conditioned by the fact that in this way you have the impression of expressing more strength on the pedals. What is needed instead is more awareness of the fact that excessive height triggers a series of problems that lead not only to bad pedalling, but also to real physical discomfort: pressure on the soft parts, irritation, pain and grazing.
Finally, a big difference between saddle height and handlebar height makes it difficult to use all the grips of the bend, with consequent problems for the shoulders and neck.
In conclusion, we can say from experience that when a cyclist is not satisfied with his/her position on the bike, very often all he/she need do is lower and setback the saddle a little in order to discover a new and much more pleasant way of cycling.