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Hi All,

Having spent the past couple months working on a project testing the aerodynamics of various bicycle components, I've done a fair bit of market research and literature review.

Long story short, bicycle manufacturers don't release any literature on the tests they have carried out, they only release a graph showing the reduction of drag without giving many key parameters to validate their claims.

When I see an advert, with a graph showing how their product is the best and a pretty CFD picture, surely some sort of actual evidence has to be provided for their claims?

What do the ASA have to say about this type of advert? Could I simply contact a bike manufacturer and expect them to give me the information about their claims (I have tried this with one manufacturer, they saithey couldnt give me that information).

Part of the reason I am asking is because it seems manufacturers are wildly over exagertating their performance benefits. My CFD and wind tunnel research, though limited, shows that their are benefits of aerodynmic drag reduction, though I can't replicate anything close to the reductions claimed by bicycle manufacturers.

To get really nerdy, they aren't giving away what Reynolds numbers they are testing at, nor the boundary layer and turbulence methods used in CFD - all of which has a very significant impact on results.

12 comments

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alansmurphy [1803 posts] 4 months ago
6 likes

Take it all with a pinch of salt, chuck it over your shoulder for luck, see how far it blows...

 

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Rapha Nadal [834 posts] 4 months ago
6 likes

If you take any manufacturers marketing claims seriously then you need your head checking!  Even the reps will admit they're all bollocks when you speak to them.

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Simon E [3299 posts] 4 months ago
2 likes

"manufacturers are wildly over exagertating their performance benefits"

Haven't they always? Honesty never sells. Tell the punters what they want to hear ("hey buddy, with my product you'll go faster without any extra effort") and they'll love you for it.

The magazine and most website reviews don't want to tell you the truth either, they don't want to have to admit that the shiny, new, supposedly 'better' version or the vastly more expensive brand makes naff-all difference.

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kil0ran [855 posts] 4 months ago
0 likes

This is why CyclingTips have a "marketing claims" score in their reviews. Of course, the average reviews site has no way of checking any of these claims, and undoubtedly the manufacturer will have controlled the test parameters to flatter their product (e.g for aero a very narrow speed window, and a similarly narrow yaw angle range). Have a look at the Hunt wheels article from last week

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Canyon48 [933 posts] 4 months ago
1 like

I've found the most annoying thing is the drag reductions are shown in grams, rather than a reduction in CdA, which I could actually verify.

And, of course, I know the manufacturers over exaggerate, as a consumer (and engineer) I don't pay much attention to the claims.

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zzk [56 posts] 4 months ago
2 likes

Sad as it may seem,  there are many gullible folk that think a new bit of kit will make them faster, rather than training harder and wiser. What is even more entertaining is that they don't learn and turn up month on month with a new bit of kit, expecting a different result!!!

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VeloUSA [250 posts] 4 months ago
0 likes

I wouldn't bother. There are too many unreleased variables which we cannot compare to a production model; wind angles. speeds, bare or production painted frame, temp ranges, frame size, rider on or off, etc. The mfg claims are probably true under their ideal conditions, conditions we consumers will never fully realize in the real world.

Granted newer frames do offer less drag than a model from, say, 7-8 years ago but that's technology advancing. If a mfg claimed we reduced drag from this 2011 model and here is why, I can visibly compare the frames and most likely agree, but not from a last year to next year model. JMO

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Canyon48 [933 posts] 4 months ago
0 likes
VeloUSA wrote:

I wouldn't bother. There are too many unreleased variables which we cannot compare to a production model; wind angles. speeds, bare or production painted frame, temp ranges, frame size, rider on or off, etc. The mfg claims are probably true under their ideal conditions, conditions we consumers will never fully realize in the real world.

Granted newer frames do offer less drag than a model from, say, 7-8 years ago but that's technology advancing. If a mfg claimed we reduced drag from this 2011 model and here is why, I can visibly compare the frames and most likely agree, but not from a last year to next year model. JMO

Yeah, that's my realisation. Frustrating as it means I have little to no significant previous research what I'm doing...

I don't for one minute doubt that "aero" products have a performance gain, I just can't compare my values to anything else.

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Canyon48 [933 posts] 4 months ago
0 likes
VeloUSA wrote:

I wouldn't bother. There are too many unreleased variables which we cannot compare to a production model; wind angles. speeds, bare or production painted frame, temp ranges, frame size, rider on or off, etc. The mfg claims are probably true under their ideal conditions, conditions we consumers will never fully realize in the real world.

Granted newer frames do offer less drag than a model from, say, 7-8 years ago but that's technology advancing. If a mfg claimed we reduced drag from this 2011 model and here is why, I can visibly compare the frames and most likely agree, but not from a last year to next year model. JMO

Yeah, that's my realisation. Frustrating as it means I have little to no significant previous research what I'm doing...

I don't for one minute doubt that "aero" products have a performance gain, I just can't compare my values to anything else.

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alansmurphy [1803 posts] 4 months ago
0 likes

Having mocked marketing and the marketing bashers; the issue is here that they won't anticipate anyone trying to replicate it .

 

As velo suggests they will probably carry out many tests and use the one that suits best, for each and every product. It may often be the combinations which give the actual gains...

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fenix [987 posts] 4 months ago
1 like

Boardman is building a wind tunnel in Evesham so you'd be able to test there.

 

TBH I dont see any aero benefits being noticeable to non professional riders.  Just buy the prettiest one. 

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Cugel [46 posts] 4 months ago
0 likes

Advertmen, eh!? They are walking euphemisms for "persuasive liars with bags of  poke-pigs done up in glamour". Does anyone believe them? Well, millions apparently - if one goes by the efforts and money put into advertising. And the tremendous numbers of ridiculous gew-gaws consumed-then-binned by must-havers all over the place.

My own pet-bete-noire is the helmet advert, which not only emits probable lies about ventilation, aerodynicalness, fashionability and other irrelevant stuff (to the supposed function of a helmet) but never anything (especially anything checkable by the consumer or independent body) about how and to what degree it will reduce harm to the head, in what circumstances.

Basically helmets are advertised in the same way as the more ludicrous womens' "fashion" shoes; and are just as dysfunctional - perhaps even dangerous to the health of the wearer, if the accident-related head damage differentials between wearers and the bare-headed of cycling accident statistics are perused. They fail in their supposed function, just like the high-heeled wobble-shoe in toe-mangler fit. But silly-billies think they "look good". Ha!

Nor do cycling magazines or websites ever attempt to test the safety functions of helmets. They are concerned only to regurgitate the manufacturer's PR blurb and pretty pics of the item atop some celebrity cyclist or other.

Cuh!

Cugel.