Viscenzo Nibali's Specialized bike fit session

CyclingNews published a gallery of photos of the Astana team getting tested for bike position by Specialized. Of particular interest was the position changes given to Viscenzo Nibali, their new star for stage races, who rode for the Cannondale-sponsored team last year. Presumibly the superior fit provided by the Specialized crew led by Andy Pruitt would improve Nibali's time trialing.

I was curious in how the position change, so I superposed the before and after photos in the article. To align the photos, I rotated and scaled them to align the arm pads.

According to the article, "Nibali's bars were raised so he could try to relax his shoulders and drop his head". However, to me if anything his "before" shot looks more relaxed, with a lower head and a more aerodynamic position. If on top of this you shift his "after" position up (the bars being higher) the advantage of the before shot appears even greater.

Of course, there's always the possibility the new position produces more power. Or there's the very real possibility the new position isn't well represented by the photo, which is just a moment in time.

Comments

jpo said…
Nice analysis, and great work on the photos. Seemed counter-intuitive to me as well. But on looking at it more closely, the position of the back and shoulders does look (very slightly) better in the After photo. The head looks a lot better in the Before shot, but that is the portion that is most mobile from second to second, and so might just be an artifact of the timing of the photos. And yeah, power production in either position is a total wild-card that is impossible to quantify from the photos.
January 29, 2013 at 6:51 PM
djconnel said…
Well, at first I thought his position may well be working. First time trial of the year, at San Luis, he was 4th. But now I just checked and in 2012 in the same race <a href="http://www.cyclingnews.com/races/tour-de-san-luis-2012/stage-4/results'>he finished second</a>. So I suppose it remains to be seen if the new bike and the new position does him any good.
January 29, 2013 at 8:15 PM
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