Karvalo wrote: ↑
Tue Nov 06, 2018 6:16 pm
youngs_modulus wrote: ↑
Tue Nov 06, 2018 5:41 pm
I’m asking what “studies” Northwestern is anticipating and why he thinks those “studies” will appear for road bikes when they didn’t for mountain bikes or cyclocross bikes.
I suspect Northwestern’s comment had more to do with self-congratulation on seeing through “marketing” and “experts” who have “education” (i.e., those who whould conduct the anticipated studies) than with any actual anticipated revelations that somehow all industry engineers have missed. I await his/her response...maybe Northwestern will surprise me.
To be fair, have you ever seen the kind of industry Whitepaper that it has become de rigeur to release along with a new aero-bike, written and released alongside a new CX or MTB? I don't remember ever seeing one, even though available frame design variables are arguably far more important to the performance and handling of a full-suss MTB than they ever will be to a UCI legal road race bike with even remotely conventional geometry.
So in that sense, if
the next gen of aero road bikes does re-include rim brake models (which I doubt) there probably would be an associated 'study' by the manufacturer of that model explaining why they are better again.
I missed this post earlier; I regret that because you've made a really great point.
Yes, I'm familiar with those whitepapers. I love them. That said, the quality varies. IMNSHO, Trek does an outstanding job with their whitepapers. They show enough of their work that I find their whitepapers highly convincing. Also, I came to engineering from a liberal arts/writing background, and engineers are (by and large) terrible writers. Trek is either paying a fantastic technical writer to produce those whitepapers or one of their engineers happens to be an outstanding writer.
I think whitepapers get published primarily because the companies that publish them have sunk a lot of money into building good R&D departments and they're trying to get the most value they can from those investments. That seems reasonable to me from a business perspective. In a way, everybody wins: otherwise-anonymous engineers get to show off their work; marketers get to market and consumers get more insight into why the company in question thinks its products are better than those of its competitors.
I may be at the center of the target audience for those papers. I'm a mechanical engineer who specializes in simulation and structural analysis, so I love reading about boundary conditions and which tools/codes the company in question chose to use. But maybe that also skews my perspective: it's pretty easy for me to tell when a company is bullshitting (not because I'm so sharp, but because they make obvious mistakes and invalid assumptions). But if I were, say, an attorney or a plumber, I wouldn't necessarily be able to tell the difference between a technical tour de force and a deeply flawed whitepaper. So maybe most consumers--maybe people like Northwest--can't easily tell how much of a whitepaper is solid engineering and how much is marketing spin. In that case, I can see how someone might conclude that the study says whatever the marketing people want it to.
And I must acknowledge that these are not peer-reviewed papers: it's possible that even the ones I really like are fabricated from whole cloth. In general, though, it's more work to fudge the data and generate flow plots that support the fudged data than it is to just do the work. It's easy to tell a small lie, but if you tell enough of them, you'll forget what you said and thus reveal all the lies. It's a losing strategy. That doesn't mean it doesn't happen, but there's some reason to think that the whitepapers, while curated, mostly represent what they claim to.
You're right that you don't see a lot of whitepapers about CX and mountain bikes. I'm pretty confident that the reason is that computational fluid dynamics (CFD) software is very expensive. A seat of CAD software like Solidworks might cost $5,000. A good FEA program that handles composites well starts at around $30,000. Decent CFD software starts there as well, and can approach six figures with enough extras. (OpenFoam, though, is a great open-source option. It can be hard to use, but third parties sell GUI interfaces to OpenFoam for about $5,000/year).
A bike company has very few capital expenses as large as analysis software. Most people (including everyone in the purchase-approval chain) thinks that Adobe Creative Cloud is expensive software ($250-$600). Solidworks is 10 times that price. CFD, at 30-100 times that price, blows bean-counters' minds. So there's a lot of pressure from executives to monetize that asset, as the B-school kids say. Because CFD software tends to be expensive--and because aero drag is nearly impossible for non-engineers to evaluate on their own--bike companies publish whitepapers on their aero bikes. FEA (my first love) is invaluable for designing cutting-edge carbon bikes, but stress plots don't excite consumers the way CFD plots do. And the kinematics of suspension are easily modeled in a general-purpose program like MATLAB. It's not pretty, but you can even model suspension kinematics in a spreadsheet. In a way, a publishing a whitepaper on suspension kinematics is like announcing that you've memorized your times tables: it's work that needs to be done, but no one thinks it's all that impressive.
Also, IME, many triathletes are well-paid professionals who think they're at least as smart as the next guy (or the next woman). There's nothing wrong with being a doctor/lawyer/management consultant, but those white papers have the same effect on that demographic as Malcom Gladwell articles: they make the reader feel smart, even if they don't actually understand what's going on. Because aerodynamics are very important in triathlon and because a plurality of triathletes are educated professionals, I suspect (but cannot prove) that triathletes lurrrve whitepapers. More to the point: whitepapers sell aero bikes. But that doesn't mean that whitepapers are just
marketing spin. And of course, there are lots of informed triathletes who know quite a bit about aerodynamics.
The flip side of whitepapers is that they expose your company's technical underbelly. I've seen a few lame mistakes in whitepapers, but in general, companies only publish them when they know they've done great work. If I saw a gross error in a whitepaper from Trek, Specialized, Zipp or anyone else, I'd shout it from the rooftops (or at least post here). I'm not the only one, either. Lots of engineers are bike people, so publishing a whitepaper with mistakes invites the ire of a thousand engineers--it would be a big mistake, and a marketing move that would backfire badly.