aero helmet? worth it? who wears one? (Page 3)

Ahhh! This is your problem. A well fit-helmet, like a Giro Advantage 2, will save you about EIGHTY SECONDS PER HOUR. Do you use race wheels? An aero lid will save you more time than they do, for $100, rather than $1,000.

I'm amazed that people that being presented with actual scientific data and formulas provided by experienced, successful triathletes and then just ignoring it because they've seen a bunch of stuff on the internet. Here's a quick summary of stuff I took issue with in this thread.

- There is no magical speed at which aero equipment or an aero position, for that matter, suddenly starts to work. Air flowing around an object doesn't start to behave differently because it's going 20 mph instead of 18 or 19.

- A slower rider will actually save more overall time than a faster rider because they're taking advantage of those aero savings longer. A faster rider will save a greater percentage of time because of the exponential nature of air resistance. The differences are fractional, but they do exist. For example: rider A does a flat 40k TT with at 175 watts, rider B does it at 250 watts. They have identical CdA's of 0.25 and it's a calm day. Rider A goes 9.72 m/s or 21.74 mph and finishes in 1:08:35. Rider B goes 11.12 m/s or 24.87 mph and finishes in 59:57. They make the same changes in equipment that lowers their CdA to 0.24 (granted, that's a pretty big drop). Now rider A goes 22.01 mph and finishes in 1:07:45. Rider B goes 11.26 m/s or 25.19 mph and finishes in 59:12. Rider A saves 50 seconds, rider B saves 45 seconds. However, Rider B has a time savings of 1.25%. Rider A's is 1.21%. But they're going over 20 mph. See?!?! Physics formulas don't care about the speed. The properties are the same.

- I put zero stock in a second hand account of what a guy on HED's production line said. Why? See above. Even assuming it wasn't in any way misconstrued, the fact that he works for HED and knows how to lay out carbon fiber in a mold doesn't mean he knows aerodynamics. And the reason they do tests at 25-30 mph is marketing. The differences are more pronounced at higher speeds so manufacturers can hype them more.

- Even after 5 years of doing triathlons, I don't understand people who say they're not going to buy aero equipment until they've improved their fitness so that it's "worth it". It's absurd to say I should train more before I go get an aero helmet or wheels or whatever. Why can't I train more AND buy the aero stuff? They're mutually exclusive and BOTH will make me faster. The aero stuff will actually make me faster RIGHT NOW.

- Aero trumps weight on nearly every triathlon course you will ever do.

- What the pros do at Kona should have NO impact on what you do at your races. In fact, many of the things the pros do shouldn't have an impact on how you race or train. Kona is a sunny, hot race and the people at the pointy end of the field are burning a LOT more energy in a much smaller amount of time than most of us EVER will. It's not surprising that they would choose a standard road helmet with better ventilation over an aero helmet. Even if you were racing Kona, I wouldn't suggest blindly following their lead. You're not going to produce nearly as much heat as they are because you won't be expending calories as quickly as they do. But to even suggest that the pros' equipment choices at Kona are a reason for AGers not to wear aero helmets is just mind-numbingly dumb.

- Finally, the OP's question of worth, as others have said, can not be answered here. It is completely individual. What are you goals, what other things could you do with that $150, etc? We can't answer those questions, only give you info on what benefit you'll get from buying an aero helmet. Only you can tell if that benefit is worth the cost.

Edited by dgunthert 2010-03-26 10:47 AM

Since we all seem to be concerned about passing runor/myth as fact, might as well note that this (aero lid saving more time than aero wheels) is NOT true in most circumstances for most people.  Watts/time saved per dollar spent?  Perhaps.  Total watts/time saved?  Very unlikely.

Didn't quote the whole thing, but nice post Dennis. This who don't believe what he (and others) posted here should do a little hard research rather than relying on internet opinions, second-hand rumor, and what "they" say.

Edited by the bear 2010-03-26 11:52 AM

link!

This piques my interest greatly

Last time I saw it I think was about 2 years ago on ST.

now I've got to go do a search over there!
gah... this is too much work

(edit) hmm found some stuff on it, mainly from mott and r10c, still hunting study though
(edit edit) found it, and John Cobb no less.
http://forum.slowtwitch.com/gforum.cgi?do=post_view_flat;post=938716;page=1;mh=-1;;sb=post_latest_reply;so=ASC
much appreciation setting me on the scent.

Edited by Leegoocrap 2010-03-26 12:24 PM

x2!
I nominate this for Post Of The Week!

x3. We seem to have had a poliferation of bad information in threads over the past few months very similar to this....

This, except not in the sarc font. I do think they look silly, but I'm sure people think I look silly much of the time.

For me, this is one of the better articles about aero setups. It's been posted a bunch of times in BT:

http://www.bikeradar.com/news/article/how-aero-is-aero-19273
 

just on the helmet front, 2 mile very smooth round loop course, dead flat, sheltered,

testing with a LG rocket got me roughly .2-.4mph

tested 4 diff times at a steady 250 watts and again at 200 watts ( approx 24mph and 21mph )

Wouldn't you get more benefit from increasing your flexibility and slamming your basebar and aerobars as low as you can comfortably tolerate while still producing about the same power. This would decrease your cross sectional area and wind resistance. This would then increase your speed.

Just seems to be an easy truly cheap way to gain speed.



Edited by crazyquick23 2010-03-26 9:13 PM

Agrere that the proper fit you describe will provide the greatest aerodynamic benefit. But it's not always easy, nor always cheap. Lots of bucks go to professional fitters and wind tunnel time to get the precise fit you describe.

Even if it were free, ??after you do that, you chase the next marginal benefit. Eventuallyyou run out of free, run out of cheap, run out of expensive, and finally run out of "worth it."

Every individual defines these levels for himself.

Edited by the bear 2010-03-26 9:20 PM

Yea I agree. I feel like a lot of people chase the "speed demon" by throwing money at the problem when more time training could gain them much more speed. Just my 2 cents.

They're both valuable resources. some people can afford the money more than they can afford the time. Who are we to judge?

Time is not always the limiter on the amount of training one can do, either.

OK then better more productive time in the saddle and maybe more of it.

So are you faster with just "better more productive time in the saddle and maybe more of it"?

Or with "better more productive time in the saddle and maybe more of it" and all the aerodynamic benefits one can buy?

As has been said several times in this thread, why not both?  I'm putting in considerably more time in the saddle this year and also picked up a new aero helmet.  The new helmet didn't make me put the bike to the side.  I mean, it doesn't even have dimples.

My argument is essentially this. For the $1500-$2000+ for wheels, aero-helmet and all sorts of aero goodies is it really cost effective at all for those of us not competing for a podium finish? Moreover, there isn't very good bang for the buck for most things. I think an aero helmet and a rear disk cover has some of the best bang for the buck out of the aero enhancements once you are already riding in an aero position.

It just doesn't seem like there's that much speed to be gained by everything else for how much you have to spend. Now that being said I don't see anything wrong with having great training and aero gear. I feel like the attitude sometimes is that if I get all this great aero gear then I don't have to work as hard to go fast. That's more of the vibe I get sometimes when people ask aero questions. Not all the time but sometimes.

Edited by crazyquick23 2010-03-26 10:07 PM

Yes.  That was an easy answer for me.  Your priorities and mine appear to be different.  I want to do everything I possibly can to go fast.  I want to train a lot, train well, and be as efficient as possible.   I figure that's the best way to a podium finish.