Flex +

Spine Flexibility and Pelvic Rotation are inextricably linked to saddle comfort—How flexible your spine is and by how many degrees your pelvis rotates determines which saddle and components fit you.


High body flexibility and no pelvic rotation whilst pedaling. You need a flat saddle.



Low body flexibility and high pelvic rotation whilst pedaling. You need a waved saddle.



Medium body flexibility and low pelvic rotation whilst pedaling. You need an in-between saddle.


    1. Introduction

    Spine Concept EVO is the result of a 3-year long study on the BICYCLE-RIDER INTERFACE, whose primary objective was to gain a better understanding of the biomechanics of bicycling and the effects that saddle and position have on the biomechanics of a cyclist.

    The study has utilized a fitting bike on which the positions of the saddle, handlebars and pedals can be independently manipulated. The bike has been custom instrumented with force transducers at the seat post, stem and bottom bracket. The goal was being able to measure those characteristics that so far have been determined only by feel. The anlysis of the huge amount of data that this study produced was the generator of our new saddle selection concept and of a new range of dedicated products.

    The initial group of experiments was performed to understand how the forces generated when pedalling are distributed on the contact points at:

    Different power outputs
    Different cadence
    Different hands position on the handlebar (Tops vs. Drops vs. Hoods)
    Different handlebar Stack and Reach

    The second group of experiments was performed to learn more about:

    Front-Rear Wheel Rider Weight Distribution (it showed substantial differences between different types of bike fitting methods). Center of Pressure Location (it defines the correct anatomical centre of a saddle).

    The final phase of the study investigated the body/machine interface more in details through: Saddle Discrimination Ability, a triangle test run to find the most reliable subjects that later performed a Subjective Rider Comfort test, which determined the relation between anatomical characteristics and shape, width of their preferred saddle.

    Multiple subjects have been taken their anthropometric/anatomic measurements and rode on a stationary bike with their own bike fitting measurements (either self fitting or commercial bike fitting). The stationary bike was equipped with several strain gauges on every contact point, a power meter and a speed/cadence computer.

    Data were recorded and analysed to determinate any existing correlation between subjective feelings and numerical results. Final report generated the Spine Concept EVO and a new range of products to better answer consumers’ needs.


    Geraint Thomas

    Geraint is a Snake. A truly long term lover of fi’zi:k saddles, Geraint’s favorite is the Arione, ever since he was killing it on the track; its flat profile helping him to achieve the perfect position for his riding style. It was using a more padded Arione that Geraint was able to finish the 2013 Tour de France despite breaking his pelvis on stage 2.

    Romain Bardet

    Romain is a Snake. Often, the skinny specialist climber goes for the Antares, but Romain’s a really flexible rider and his saddle of choice is the fi’zi:k Arione. He especially likes the stiffness of the 00 option, which powered him to another Tour de France stage win, and GC second place.

    Rohan Dennis

    Rohan is a Snake. Rohan has used the Arione for his whole career. He used this long, flat platform to smash the hour record in Berne as well to take the yellow jersey at the Tour de France. Rohan likes to switch his position back and forward on the long stages, and the fi’zi:k Arione provides him with a solid, fixed position when pushing to the limit.

    Bernard Eisel

    Bernie is a Bull. One of the most respected riders among the peloton, Bernie’s an all rounder, and is known as one of the wheels to follow in any sprint. He loves attacking the cobblestone and his saddle of choice is the fi’zi:k Aliante – he’s put it to the test it many times here in Italy, riding our Granfondo.

    Daniel Oss

    Daniel is a Bull. He’s like a rockstar – especially when he rolls over the spring classics and rocks up the TTT where he’s bagged a couple of world titles and a TdF win. For his neat, efficient riding style Daniel needs a supportive saddle –that’s why he goes for the fi’zi:k Aliante. He was the first rider to switch from the old to the new Aliante model.

    Tejay Van Garderen

    Tejay is a Bull. There’s no doubt he’s a really determined, strong-minded rider, he keeps fighting and never gives up. We’ve shared the road together since his HTC days – through climbs, breakaways time trials, and grand tour stage wins – and proved that the fi’zi:k Aliante is the perfect fit for Tejay.

    Chris Froome

    Chris is a Chameleon. By far the most successful GC rider in the peloton today, he’s a special kind of winner. Whether or not you like his unique riding style you can’t argue with the fact that he’s way faster than anyone else! Chris fell in love with the fi’zi:k Antares at our very first Mallorca training camp together, and now we’re quite used to making his yellow option in July.

    Alejandro Valverde

    Alejandro is a Chameleon. Although he’s one of the most experienced riders in the peloton we only got to know each other just few years ago. The Antares was a natural choice to match his really aggressive riding style and all-terrain character. Classics, grand tour podiums, time trials, points competitions, world championships… Alejandro puts his fi’zi:k Antares to the test whatever he faces.

    Greg Van Avermaet

    Greg is a Chameleon. Watching him is always exciting; whether it’s a cobblestone classic or a grand tour stage, Greg will probably be in the front, pushing the pace and looking to break away from the peloton. The wide, slightly curved profile of the fi’zi:k Antares affords him as many position options as he needs to match his “true chameleon” riding style.

© 2016 SELLE ROYAL SPA - SOCIETA’ A SOCIO UNICO. All Rights Reserved