The seat is by far the part that most of all affect the position on a bicycle. The possible settings allow you to change the orientation, height, and retreat.
Align the seatorientation assumes the position of the saddle seat perfectly aligned with the bike. Attention because subtle inaccuracies can significantly alter the ride so if you can not "find the position of the first check is to do just that.
Even more delicate is the orientation of the saddle on the horizontal plane.
say that the seat must be perfectly horizontal (or "bubble" referring to the level) is not always correct.
Meanwhile, we must consider the type of saddle. Some models show a rise in the back and should be taken into account. If you want to use the spirit level should be pointing the instrument at least one or two centimeters ahead of the rear edge.
Incorrect adjustment of the seat in this way can cause numbness if the tip is too up, or excessive fatigue of the arms if the rider's weight is slid forward.
The correct height
The table on the right to be regarded as indicative and part by measuring the height of the horse rider . This measure is multiplied by 0.65 (0.55 in the case of mountain biking) to get the approximate length of the column, to 0.885 for the height of the indicative saddle from the bottom bracket and 0.635 for the indicative distance between the tip of the saddle and handlebars.
Another less scientific method involves setting off on a bike and adjust the seat height so that it touches the pedal with the heel leg fully stretched at the point most of the pedal away from the support saddle. This determines that,
once the pedal is engaged it creates an angle of about 20 ° behind the knee. This value should be measured with the foot parallel to the ground (note: the pedal, not the foot because the shoes and shaped to hold the foot in a natural position of thrust and non-flat). One advantage of this system also include the natural compliance otherwise impossible to assess the seat at the table. Each seat, in fact, when subjected to the weight of the rider absorbs slightly by the shape, in fact, lower the seat. Obviously, every seat model behaves differently over time and even this can go to increase compliance.
Receding Seat
is the real crux of the adjustment of the seat. The decline, to some extent, affects more than the height of the seat position while being clearly related to this one.
First of all the terms used should be clarified: the retreat of the saddle is given by distance between parallel lines, perpendicular to the ground, passing through the tip of the saddle and the center of the bottom bracket.
It also said that the variety of saddles on the market can affect this measure, so if you change your seat model this value can vary given the different sizes in length and curvature of the hull. For this reason it is more useful to consider the anatomical center the seat (usually considered about 12 inches from the rear).
- A bit 'of teoria
Determinare l'arretramento corretto della sella significa trovare l'angolo di spinta migliore tra anca e movimento centrale. Per stabilire questo valore andrebbe analizzato il movimento del piede e della caviglia. Se, infatti, l'asse del pedale si muove disegnando un cerchio attorno al movimento centrale così non è per la caviglia. La variabile "piede" che c'è tra questa e l'asse del pedale determina un movimento ellittico della caviglia.
Di fatto questo si traduce in una fase di spinta ideale tra "ore undici e ore sette" immaginando il cerchio disegnato dall'asse del pedale sovrapposto al quadrante di un orologio.
E' importante che il piede si trovi a spingere con la giusta angolazione altrimenti non si sfrutterebbe al meglio l'allungamento e la compressione dei muscoli durante lo sforzo
Mettiamoci in posizione
Per determinare il migliore arretramento di sella occorre avere il ginocchio sulla verticale dell'asse del pedale quando questo è nel punto più avanzato rispetto al movimento centrale.
La tabella schematizza i valori della distanza tra sella e movimento centrale. Piccole variazioni si possono avere a seconda dei soggetti e anche in caso di modifica della lunghezza delle pedivelle.
75 -66,4
76 -67,3
77 -68,1
78 -69,0
79 -69,9
80 -70,8
81 -71,7
82 -72,6
83 -73,5
84 -74,3
85 -75,2
86 -76,1
87 -77,0
88 -77,9
89 -78,8
90 -79,7
91 -80,5
92 -81,4
93 -82,3
94 -83,2
95 -84,1
96 -85,0
97 -85,8
98 -86,7
99 -87,6
100 -88,5