damon_rinard wrote:
Not really replying to you Jack, just needed a place to jump in. ;-) Bear with me, I'll get to the 9 Watts.
On the way back from my bike ride today (beautiful weather, beautiful roads, beautiful riding in southern Ontario this time of year. I'd missed it the last two years since I was France this week during those years...), I was listening to a book on CD,
Guns, Germs and Steel by Jared Diamond. In this chapter I heard he was trying to explain why some cultures seem to be open to innovation and some don't. Lots of reasons suggested, one of wich struck me: some societies are culturally more resistant to innovation (for a time, as apparently this can change over the centuries). I won't bore you with the examples, but it reminded me a little of aspects of Slowtwitch forum, which is I guess is a kind of society in itself. If I understood Diamond, he seems to explain that some of the world dominance displayed by the societies who were more open to innovation (warfare, exploration, colonization, etc.) could be attributed in part to their creative inventions (or swift adoption of inventions from other societies).
Anyway, I wonder if we might have something like that going on here.
After all, for years I was a weight weenie. I worked at Kestrel in the late 80s and early 90s and I weighed nearly all the bike parts in the world (well, in my world at least). It wasn't until years later (and an engineering degree), as well as exposure to plenty of people a lot smarter than me, that I finally "got" aerodynamics with bikes. Because of my own life experience, I don't expect every reader to "get it" the instant Cervelo issues a new white paper.
Anyway, the 9 Watts are a simple calculation from the difference in drag reported by the wind tunnel. They're real. I'm happy to answer any questions that might help anyone understand that.
Also, remember the 32 Watts is "up to" 32 Watts - that's the top of the range of typical road bikes. There's a roughly 10 Watt spread among typical road bikes. This is all illustrated in the chart in the white paper.
These Watts are real whether you or I or anybody else believes it or not. We measured it.
Ask me about it.
Damon, replied to you, but it's a general reply:
Damon, Jack, and Tom, Just to be clear, I have absolutely no bone to pick with either innovation or the measurements that Cervelo has produced to show how well the S5 performs. I'm not qualified to debate or contest them, and I tend to believe them.
What I do take issue with, and was trying to get across in my earlier post, is that where data stops and people try to translate that to real-world impact, the correlation gets foggy. Yaw angles change. How much time one spends riding on someone's wheel changes. How much time a rider spends sitting up, the tautness of their jersey, whether they're wearing a livestrong bracelet or gloves, their aerodrink straw, the frame comfort, weight, tubular preference, fork type, wheel choice all also make a difference. And to some degree, are codependent. That's where my issue shows up.
If 'drag at x% yaw' is the measurement, fine. Let's leave it there. The moment the groupies jump on with emotional, straw man arguments like 'wouldn't So-and-so have wanted x seconds in time trial x', they've ignored 700 factors that could also have given the rider those seconds, ignored aspects of the S5 that might not have given them those seconds because the testing protocol assumptions didn't line up with the details of that ride, and presumably to make the folks on the forum believe that the bike is the preferred way to get those seconds. It's huckerstish and myopic, and appears on a message board where the owners and key contributors all have an interest in the bike industry being healthy and consumers spending more. And for MOST triathletes, a bike is the most expensive solution. The bias wears on me, and I apologize for that.
And Cervelo, Specialized, Trek all spend hundreds, thousands, how many ever dollars framing their message. I tried to provide a counterpoint, that if I summed it up, might be:
- Cervelo's S5 is slipprier, to the tune of some number of watts
- The number of watts will vary based on how you use the frame, and what you surround the frame with (rider, wheels, forks, yada...).
- I contend that number of watts is insignificant for most athletes, and comes at a premium price. There are other options that are more cost effective - for most athletes. That's my judgment. I'd likely have that same judgment for any 9w gain published in a white paper with a ton of assumptions.
- Trying to show exactly how much time a rider will save on a given day or situation....or in past situations for pros...is fruitless. The assumptions never line up.
- The S5 should be considered for what it is: an alternative to go faster, like 600 other things.
- Claims about pro results, what-if's for past situations if they'd used a slipperier frame are hype, nothing more. The causals aren't there. For me.
Lastly, Dan/RChung/Jordan/Tom: It seems to me that the critical issue here is that the consumer DOESN'T KNOW what to buy based on test results. Asking an athlete to figure out testing protocols, yaw angles, drag, rolling resistance, interaction between fork and frame, laminar flow isn't where it's at. Hell, retailers may or may not have time to dig into it to really understand it, given most carry multiple brands.
With Slowtwitch as a go-to source of information about the triathlon industry with close ties to the manufacturer and retail industry, it seems that ST is in a perfect position to suggest a standard or a single set of standard measurements could be used to answer the questions that the consumer is frankly tired of trying to answer for themselves. Think of it as consumer reports for Triathlon / TT. That's the gift that Manufacturers and ST could give the consumer, because that's what we want.
I'm not sure the industry wants that, though. Just thinkin' out loud. Continue to flame away.
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- I do all my own stunts
