How to position the saddle properly: it seems easy and obvious, but try pedalling and you will realize how this topic cannot be underestimated.
We will try to outline some advice in order to avoid the most common mistakes and provide some suggestions on how to find the right position; everyone has a different cycling position.
The seat setback
Perhaps the most important phase which is often overlooked, also thanks to some inexperienced retailers, is that when selling a bike the position of the saddle is omitted. Seat setback is a fundamental aspect for both comfort and performance. The setback depends a lot on the length of the femur and, roughly – without the availability of computerized tools – must be calculated with a plumb line that aligns the middle of the kneecap to the middle of the pedal pivot. In order to obtain this information it is best to have warmed up a bit beforehand so that the position is as natural as possible.
Here follows some indicative data: the tip of the saddle must fall at least 4cm behind the bottom bracket, the cranks. This is not only a biomechanical datum, but is also part of the UCI racing regulations. On average, a person about 1.80 m high will have a seat setback of 7.5 cm / 8.0 cm between the middle of the bottom bracket and the tip of the saddle. Mountains bike cyclists tend to place the saddle a few millimetres further ahead so as to facilitate riding downhill with the weight shifted behind the saddle and also for shifting the weight forwards in steep uphill climbs.
Having worked out the setback, we can focus on the saddle height. It is important that the knee be slightly bent, therefore not fully extended, and the foot must be flat at the bottom of the pedal stroke. A saddle that is too high can lead to an incorrect hip movement that can cause inflammation in the lower back, whilst a saddle that is too low can, in the long run, lead to knee pain.
Once again: the setback and height are at the heart of the cycling position; only after having established these parameters can we focus on the length of the bike and the handlebar reach. The latter is a parameter that must be found taking into consideration the difference in height between the saddle and the handlebar: a high handlebar will give the idea of a longer bike, while a lower handlebar can often be difficult to reach comfortably. It takes a compromise, which is found only after various attempts. An external viewpoint can help a lot in assessing the angle of your back and arms, but what ultimately makes the difference is one’s personal feeling. Whilst the distance between the saddle and the handlebar is important for road bikes for comfort and aerodynamics, it is less so for mountain bikes and it must also be set according to the different tracks: the extreme cross country cyclist who rides up very steep climbs and down deep descents will prefer a shorter bicycle with a fairly high handlebar, whilst the cyclist who rides long distances on easy roads will prefer a slightly longer bike with an accentuated compromise in length and handlebar height.
A short comment on the racing bike’s handlebar width: the reference measurement is the width of one’s shoulders; recently the trend is that of using wider handlebars, a trend inherited from mountain bikes. But be careful, because if, on the one hand, the wider handlebar may improve the opening of the diaphragm and therefore help in breathing, on the other hand, the aerodynamic coefficient worsens. Once again, the right compromise is necessary.
Although sports science is increasingly refined and scholars adopt mathematical methods to find the best bike position, we must remember that our body is a set not only of levers but also of different elastic factors and personal motor skills. Trust the expert, but also trust your own personal feelings.