Dear bike industry, please can we stop making claims about products being ‘aero’ without providing evidence to back them up.
It’s been a fun ride, but from this day forward, I will no longer be humouring press releases that claim [insert tiny bike part here] is ‘aero’ without any data or evidence of testing to substantiate it.
It’s almost Christmas, so I shouldn’t be this grumpy, but before we part ways and enjoy the holidays, I need to get this rant off my chest.
The bottom bracket that broke the camel's back
What prompted this outburst, you ask?
Well, Tadej Pogačar got a new bottom bracket yesterday from team sponsor, Bikone – the snappily named ‘BSA Road Ceramic Aero UAE Bottom Bracket for Shimano’.
Like the mythical Dominator (the greatest bike ever made), there are no superlatives spared in the press materials for this set of €349 bearing cups.
It is, for example, claimed to take “marginal gains taken to the next level”, and to be “the most ambitious evolution of the collaboration between Bikone and UAE Team Emirates”.
Aimed at riders who “demand” – not simply want – “maximum performance”, Bikone claims this latest bottom bracket is a whopping 17g lighter than its previous iteration and aerodynamically optimised, thanks to a “completely smooth exterior” on the non-driveside bearing cup.
This has been achieved by moving the installation notches to the inside of the cup (which, you guessed it, means it requires a proprietary tool to install it on your bike), and is said to result in reduced “airflow turbulence around the bottom bracket area”.
Unfortunately, though, Bikone has not provided any data to quantify the potential performance gains from this design, or even any evidence of CFD modelling, wind-tunnel testing or so on. And going on the vibes of comments sections here on BikeRadar and elsewhere, I don’t think anyone believes this stuff anymore.
Thanks to wide availability of information nowadays, riders are, generally speaking, far more savvy and informed when it comes to these subjects than ever before.
BikeRadar’s readers are, in particular, known to be among the most savvy and erudite people on earth (so well done you).
Given this, even brands that show their working, and provide data and evidence of proper testing during development, are rightly subject to detailed scrutiny when making performance claims.
It therefore baffles me that some brands seemingly still think they can insert the word ‘aero’ into a press release and expect everyone to take it at face value.
Why single out one brand?
I know I shouldn’t get so worked up about this. Aside from the fact it’s almost Christmas, this is, after all, how marketing works.
Companies make products, marketing teams help them sell those products. It’s not that deep.
It’s also fair to say that the fact that data hasn’t been provided to us at BikeRadar doesn’t mean that none exists. When asked, Bikone says the aero claims have been “validated through extensive real-world testing” with Pogačar’s team, but that “detailed data related to aerodynamics, testing protocols, and potential wattage savings” are confidential.
Whether that means the gains are so enormous that UAE Team Emirates doesn’t want to tip off its rivals, or they’re so tiny they don’t make for great marketing copy, I guess we'll never know.
Whatever the truth of the matter, though, the word ‘aero’ gets attached to all manner of bike-related things these days, so I don't think it should be any surprise that many will scoff when seeing it used to describe yet another part.
Most of us, after all, can appreciate intuitively why aero road bikes such as the Cervélo S5 or Factor One are more slippery than climbing bikes such as the Cervélo R5 or Specialized S-Works Aethos 2. But, as things get smaller and more insignificant, it’s harder to suspend your disbelief when brands make unsubstantiated claims.
Word salads such as ‘aero socks’ and ‘aero baselayer’, for example, stretch credulity until you see data that shows there may be something to them.
The problem is that, unlike weight, aerodynamics are complicated. Small things can make a difference, even if it’s not always obvious at a glance.
I’m therefore not arguing against the concept of an aerodynamic bottom bracket (although I might playfully ask whether a press-fit bottom bracket – which can be hidden almost completely inside the bike frame – might be even more aero). But, if you’re going to make one, and then try to sell it to people for €349, it’s not unreasonable for people to ask you to show your working.
To cite an example of when a brand did it the right way, POC caused much consternation in early 2023 when it launched the CFD-developed Propel sunglasses – “the most aerodynamic cycling sunglasses” it had ever produced.
At face value, ‘aero sunglasses’ sounds slightly ridiculous, but POC at least provided an image from its CFD modelling and supplied a guideline for the potential performance gains on offer – “low single [watt] figures when riding at 40kph” and dependent on the rider’s position on the bike.
Even with this tiny amount of evidence, riders are empowered to make their own mind up about whether such a potential gain is worth the financial outlay.
Without this kind of thing, though, it’s hardly surprising many riders feel the bike industry is too often trying to dress products up with performance claims that won’t make any tangible difference.
So, brands, consider yourself warned. From here on out, those that fail to show their working will be sent straight to detention and issued with 100 lines of “I must substantiate aerodynamic claims”.
