Difficult to see clearly but, it seems that Miranda Carfrea is going for the Eiffel tower option …
J’imagine très bien Jim Felt se dire… merde on va dépenser combien déjà pour faire le moule du DA en 49″ 650… juste pour elle… alors qu’elle pourrait être sur un 51, tête de mule! Mais Jim, ca va plus vite le 650 :-p
Le pire c est que c’est retul approuvé…
Once Carfrae received her new DA, there were still a few changes to be made. The front end was dropped down one centimeter, and the armrest moved forward one centimeter, giving Rinny more drop and reach. Cranks were changed to 165 (she was previously riding 167.5). Studies have shown that maximum power output is not affected by crank lengths ranging from 120-220 (Martin et al 2001). There is a significant biomechanical advantage to using shorter cranks in the TT position. With shorter cranks, the athlete can ride a more aggressive position without closing off his or her hip angle at the top of the stroke.
This year, by switching to shorter cranks, we will attempt to decrease Rinny’s back angle while preserving hip angle. Looks can be deceiving with her current position. She has a 21 degree back angle (most top level pros are around 19-23 degrees), but with her morphology, going lower closes off her hip angle, even when it appears she is very upright. Rinny will be visting the wind tunnel in a few weeks and we will be able to determine if going lower is actually a faster position for her.
There is a lot of « cycling tradition » involved when a fitter considers changing something that seems so commonly accepted, such as crank length. Not all athletes will want, or should move to cranks as short as 165, but should consider going shorter than what they are using. I plan to introduce more athletes to shorter cranks in 2011 to see the response. Based on Carfrae’s fit data she could use something shorter, but the exact length is to be determined (145-155). She has too much range of motion at the knee and could benefit from having a more open hip angle. With the proper documentation and presentation of fit data, Carfrae could become the driver for smaller female athletes to use shorter cranks.
Je n’ai pas lu la partie de l’article en Anglais, mais je ne suis pas d’accord sur l’opposition 700/650.
Dans le cas de Carfrae, il est à peu près certain qu’elle sera mieux posée sur le 48 (ou 49 chez Felt ?) en 650 que sur le 51 en 700. La géométrie est bcp plus adaptée à sa morphologie, si elle veut avoir un drop suffisant pour être le plus aéro possible.
Par contre, d’accord pour dire que la position actuelle est largement perfectible.
Moi, quand je regarde sa position… elle me donne l’impression d’avoir un vélo trop petit mais bon.
si deja elle n’avait pas les coudes dans l’axe de la douille de direction cette impression serait attenuée 😉
une potence de minimum 60mm donnerai deja quelque chose de mieux a mon avis 😉
la rumeur dit que la potence est custom made… juste pour elle!
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Difficult to see clearly but, it seems that Miranda Carfrea is going for the Eiffel tower option …
J’imagine très bien Jim Felt se dire… merde on va dépenser combien déjà pour faire le moule du DA en 49″ 650… juste pour elle… alors qu’elle pourrait être sur un 51, tête de mule! Mais Jim, ca va plus vite le 650 :-p
Le pire c est que c’est retul approuvé…
Once Carfrae received her new DA, there were still a few changes to be made. The front end was dropped down one centimeter, and the armrest moved forward one centimeter, giving Rinny more drop and reach. Cranks were changed to 165 (she was previously riding 167.5). Studies have shown that maximum power output is not affected by crank lengths ranging from 120-220 (Martin et al 2001). There is a significant biomechanical advantage to using shorter cranks in the TT position. With shorter cranks, the athlete can ride a more aggressive position without closing off his or her hip angle at the top of the stroke.
This year, by switching to shorter cranks, we will attempt to decrease Rinny’s back angle while preserving hip angle. Looks can be deceiving with her current position. She has a 21 degree back angle (most top level pros are around 19-23 degrees), but with her morphology, going lower closes off her hip angle, even when it appears she is very upright. Rinny will be visting the wind tunnel in a few weeks and we will be able to determine if going lower is actually a faster position for her.
There is a lot of « cycling tradition » involved when a fitter considers changing something that seems so commonly accepted, such as crank length. Not all athletes will want, or should move to cranks as short as 165, but should consider going shorter than what they are using. I plan to introduce more athletes to shorter cranks in 2011 to see the response. Based on Carfrae’s fit data she could use something shorter, but the exact length is to be determined (145-155). She has too much range of motion at the knee and could benefit from having a more open hip angle. With the proper documentation and presentation of fit data, Carfrae could become the driver for smaller female athletes to use shorter cranks.
Je n’ai pas lu la partie de l’article en Anglais, mais je ne suis pas d’accord sur l’opposition 700/650.
Dans le cas de Carfrae, il est à peu près certain qu’elle sera mieux posée sur le 48 (ou 49 chez Felt ?) en 650 que sur le 51 en 700. La géométrie est bcp plus adaptée à sa morphologie, si elle veut avoir un drop suffisant pour être le plus aéro possible.
Par contre, d’accord pour dire que la position actuelle est largement perfectible.
Moi, quand je regarde sa position… elle me donne l’impression d’avoir un vélo trop petit mais bon.
si deja elle n’avait pas les coudes dans l’axe de la douille de direction cette impression serait attenuée 😉
une potence de minimum 60mm donnerai deja quelque chose de mieux a mon avis 😉
la rumeur dit que la potence est custom made… juste pour elle!