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An analysis of drop

Posted: Thu Mar 21, 2013 6:02 pm
by AGW
After reading James Huang's pro bike review of Philipe Gilbert's SLR01, I started crunching some numbers. I believe I've found Huang's indignation to be misplaced and mistaken as evidenced by his own previous reviews of Gilbert's Canyon prior to joining BMC. To wit:

Gilbert's 2013 SLR01:
Size 50, Stack/reach 530/378
535mm TT + 140mm -6* stem = 675mm total reach
Setback 59mm, tip of saddle to handelbars 581mm
Drop 122mm

Gilbert's 2011 Aeroad:
Size 56, stack/reach 555/396
560mm TT + 120mm -6* stem = 680mm total reach
Setback 75mm, tip of saddle to handlebars 587mm
Drop 115mm

Gilbert reduced his total reach by 5mm, dropped his bars 7mm, and moved 16mm closer to the BB. In other words, despite a 25mm difference in stack height, his position on the Team Machine differs at most 16mm from that of his larger Aeroad. The magic of a 6* stem angle! Had he replicated his BMC position on his Canyon by reducing his spacer stack and using a 115mm stem or some handlebars with shorter reach, Huang would likely have kept his mouth shut. Instead he used Gilbert's bike as a springboard to soapbox SlamThatStem. :thumbsdown:

To be honest, he doesn't look any different on two bikes either. Hunched over and slogging, as usual.

Image vs Image

And now, another analysis of pro averages:

Image

And a link for djconnel: https://docs.google.com/file/d/0B1JPD57r2HyrV1IxUGZtNTVWcGM/edit?usp=sharing

An analysis of drop

Posted: Thu Mar 21, 2013 6:02 pm
by Weenie

Re: An analysis of drop

Posted: Thu Mar 21, 2013 6:14 pm
by GT56
it does make sense that his drop has increased though, he's grown taller by 1 cm since 2011!

Re: An analysis of drop

Posted: Thu Mar 21, 2013 6:22 pm
by AGW
A quick disclaimer: I realize that this is a very amateurish analysis that is probably failing to take into account a number of things re: geometry, but this certainly goes a lot further than Huang's diatribe. Anyway, I'm trying to get the conversation started.

Dan Empfield from Slowtwitch found that pros (or at least the ones from Mediterranean countries) have a drop-to-saddle height at around 11%, so I'm not sure why my average is higher. I based them on Huang's measurements which he seems to get from the team mechanics. Also note the difference between Garmin riders and the rest of the riders on the list with the exception of Hesjedal. Vroomen's "raise the bars" philosophy gives them no choice!

Re: An analysis of drop

Posted: Thu Mar 21, 2013 6:52 pm
by lyot
Nice post !

Re: An analysis of drop

Posted: Thu Mar 21, 2013 7:08 pm
by KWalker
Yah a bunch of your seat heights are wrong. The new Ride has Gilbert's seat height much lower.

Re: An analysis of drop

Posted: Thu Mar 21, 2013 7:18 pm
by AGW
Doing my best with the source I used. Care to contribute? The way Gilbert seems to switch between an Arione and a classic Flite might also skew height measurements.

Re: An analysis of drop

Posted: Thu Mar 21, 2013 9:43 pm
by djconnel
Nice post (and thanks for the data link)! So Horner is the fatty master in the crowd. I felt like a slacker after yesterday 3D Bike Fit took me to 8 cm drop with 72 cm BB-to-seat-top.

Horner on hoods:
Image

Ryder (drop winner):
Image

Wow -- Ryder's back looks as if it's going to break in half.

Re: An analysis of drop

Posted: Thu Mar 21, 2013 10:00 pm
by KWalker
Don't have time to contribute- but RIDE's pro bike features will ad like 16 bikes to that list. Just re-google search as some of the others off the top of my head don't seem right.

Re: An analysis of drop

Posted: Thu Mar 21, 2013 10:09 pm
by SolidSnake03
Ryder looks like he is bending at the back/using back flexibility to manage the drop vs. Rotating the pelvis and hips, not going to get into it more but that seems to be a possible reason for the painful looking back bend

An analysis of drop

Posted: Thu Mar 21, 2013 10:29 pm
by ultyguy
I thought the same to dig up Gilbert's Canyon measurements after that piece cause he never looked anywhere near extreme position wise on it. He does look worse on the bmc, cramped.

Re: An analysis of drop

Posted: Thu Mar 21, 2013 10:39 pm
by headwind816
Maybe his preference is a bit short versus long. I know that is my preference. I think Horner is more in tune to his body and able to shake stereotypical bike set ups to maximize his comfort. Ryder's set up looks to maximize the low, areo position and not hood riding. Disclaimer, this is me writing my thoughts :-)

Re: An analysis of drop

Posted: Fri Mar 22, 2013 12:21 am
by fa63
I have been collecting published data on pro's bikes for a few years now. What I have found is there seems to be a somewhat decent correlation between rider height vs. saddle height and reach to handlebars, especially when you take into account variations due to possible measurement errors and errors in published rider heights (people tend to be shorter than they think, usually). That said, drop tends to be more scattered, centered around 12 cm or so, and is not really dependent on rider height.

Re: An analysis of drop

Posted: Fri Mar 22, 2013 2:16 am
by Wingnut
Like us I believe that even the Pro's get it wrong, just because it feels or looks right doesn't mean it's efficient or theoretically correct....

Re: An analysis of drop

Posted: Fri Mar 22, 2013 8:44 am
by CarpetFibre
Wingnut wrote:Like us I believe that even the Pro's get it wrong, just because it feels or looks right doesn't mean it's efficient or theoretically correct....


I disagree. I think the most important thing is first you ride in a position that feels right, and then the body is very good at adapting to that position and becoming efficient in it. I know that riding a different shaped bike feels weird at first - you can't pedal smoothly or lay down power correctly - but you can often get used to it eventually right? I'm not saying you can get used to anything, sure there are things that end up being mistakes for you.

That's what I find with most stuff on the forums, when people argue about optimum seat height, crank length, handlebar width etc etc... At the end of the day you have people who swear by this and swear by that. Doesn't anyone take home the message that it's about what you've become used to? 165mm cranks may well work for someone just as well as 180mm cranks work for someone else.

Re: An analysis of drop

Posted: Fri Mar 22, 2013 9:00 am
by thisisatest
If the cranks were behind my ears, no amount of time will get me to produce efficient power. You have an adapted maximum power in any position, but one position (or a range, or even two ranges) is better than others. An optimum, if you will. And pros can get caught up in peer pressure, position fashion, etc. They are still mostly human, after all.

Re: An analysis of drop

Posted: Fri Mar 22, 2013 9:00 am
by Weenie