You keep using that word. I do not think it means what you think it means.

I disagree. Just one standard.
Once you start including exceptions you open the door for confusion and manipulation.
Besides, it should be utterly unnecessary. As long as the P5 is one of the bikes tested you can compare it's data with that for other bikes to your heart's content. That's the whole point - and doing it this way means the data may actually be trustworthy.

There are a lot of concerns to address, which some have already posted (i.e. regarding weightings and reported units etc.) but if I were tasked with drafting a proper standard, I'd do my best to understand:

• How companies/people "game" current tests (see SAE bHp, EPA mileage, etc., Emissions testing *cough* VW),
• That regulations can influence development in unintended ways,
• Language must be strict, clear, and unambiguous (shall, must, will...),
• "Stakeholders" must find it attractive, or the standard will not be adopted.

There would have to be a cost for a certification of compliance, and records kept such that an interested party could challenge the results and even issue fiscal penalties along with retractions for faulty testing or falsification of results. Otherwise we're playing house here. The end users (consumers and companies alike) would have to trust that the standard is meaningful else it's like a degree from a for-profit school nobody respects.

I think my vision is a little less formal. We will have set protocols for testing and reporting, will certify our own independent results, and will expect the publication of those results to me made in a specific manner. What I believe will happen is consumers will be more trusting of such testing and demand it from the manufacturers. Should an industry-wide set of agreed upon protocols for testing and reporting come out of that, so be it. We will not stray from our goal of completely independent testing. In fact, one of our rules will be not allowing manufacturers to be present during testing. In fact, that's one of the ways they'll save the most money; no travel expenses.

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Jim Manton / ERO Sports

Jim, your aero pledge signature makes me ask the question; what's the point of coming up with a standard if the test results can't be universally applied to athletes? A manufacturer could publish data using a protocol standard but their results mean diddly until I test it on myself. Just because a standalone component tests faster than its competitor, we don't really know how it interacts in the complete setup. Too many variables, not enough $$ and time.

One additon: test, using two different speeds. Remember how the p-09 helmet performs faster (and differently) with "plug in" at a certain speed? Because, that.

I believe Cervelo have a P2K bike (with its own special case) for testing all their bikes against.

As Cervelo pretty much started the aero bike market, how about using their P2K as the benchmark? All bikes should be tested against a standardized bike and wheel combo, and use the standardized wheel, with and without a standardized mannequin. In an ideal world, there would be static and dynamic tests (mannequin). Rolling road becomes another issue, but for standard testingThey should be tested at standard wind speed and yaw angles. Since bikes aren't completely symmetrical, (+) and (-) yaw angles should be tested. Weighted average for performance should all use the same weighting calc.

All wheels should be tested on the same identical bike, and should be tested at standard wind speed and yaw angles. Weighted average for performance should all use the same weighting calc, preferably the same as for bikes. Mannequin can be static and/or dynamic as for bikes testing

Items like helmets should be.....wait for it.....tested at standard wind speed and yaw angles. Weighted average for performance should all use the same weighting calc, preferably the same as for bikes.

Standardization is the first hurdle, deciding what the standards should be is hurdle 2 and relevance to real world is the final step. There is a sweet spot of cost/repeatability/validity etc. The current ad hoc testing isn't very useful to us consumers, but ideal testing could end up being cost prohibitive.

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TriDork

"Happiness is a myth. All you can hope for is to get laid once in a while, drunk once in a while and to eat chocolate every day"

This is exactly what I was thinking. Something testing faster than something else and that being applied across the board for many different riders at many different speeds is a claim that is virtually impossible to validate. That makes the claim useless.

Reporting in power is annoying, but it's basically the exact same problem as "time savings over 40km", it's relative.

I would like to see testing done at the speed an athlete actually buying the thing races at.

Ehhhh, not really. Time saved over 40km applies almost universally, while drag power saved is definitely different for riders of different speeds. 5W saved at 30mph is less at 20mph, but 10sec/40km saved at 50km/hr is essentially the same as at 35 km/hr.

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__________________________

I tweet!

Jim,

I'd really appreciate if we could back up a bit to assess the benefits of in-velodrome vs wind tunnel testing.

i.e. what does one give that the other doesn't.

If this information is already out there, I am happy for a link to teach me.

Thanks for your help. I always appreciate your posts.

Randolph

When you double the velocity, drag increases fourfold. That seems highly unlikely.

When you ride 40km at 35kph instead of 50kph, you have a longer time period in which a smaller reduction in resistance (either expressed as a percentage or as absolute required power) can and does yield a greater absolute time saving.
e.g 28.8sec off 48 minutes is 1% faster, a mere 0.8% off 1:08:34 would be a saving of 33 seconds. Cervelo website has some fully worked examples?

when you half the velocity, the time savings increase

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Eric Reid AeroFit | Instagram Portfolio
Aerodynamic Retul Bike Fitting

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I cant speak to the specific engineering requirements of aero testing for bikes.

I do know a little about setting global standards for performance testing for an entire industry. I suspect that the difference between setting an international industry standard which is a mandatory requirement for businesses if their country is a signatory to a set of international regulations, and your own proposal, is that there is no means of compelling companies to work to a standard that they know may not benefit them.

I would think that the minimum standard or proposed standards are set out as a white paper for an industry wide user group to consult upon, that the proposals allow for both self certification and for you to conduct testing on companies behalf. This is subject to audit and verification but the signatories are not compelled to use you.

I think there are two different issues at work here. the first is setting a standard that can be accepted and adopted. The second is offering a deal as an independent test house.

The former requires consultation with stake holders. The second is simply a deal that you can offer people.

One should not be a prerequisite for the other. International standards are divorced from specific providers such as independent test houses, but well respected independent testers have solid businesses because they are respected for their independence.

I would think it would benefit the industry to work towards adopting a standard, but given that they can not agree on disc brakes, bottom brackets in terms of setting a standard, and certain manufacturers are so obtuse with respect to their wind tunnel testing results I would not hold my breath waiting for a standard thats accepted to be forthcoming