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Bicycling Mag - Speed Secrets of Rocket Scientists?
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There is an article in the September issue of Bicycling Magazine where they interviewed the members of MIT's time trial team. These guys won their regional TTT championship in April and work with Cervelo and Ivan Basso on aerodynamic studies (according to the article).

Among their comments relating to aerodynamics:

1) "A non-aero helmet creates four times the drag of a non-aero wheelset. So you can spend $2000 on a wheelset, or spend $200 on a helmet and be faster."

2) "How you put your race number on matters more than having an aero wheel."

3) "On a round-tubed frame, having a bottle on your seat tube is more aerodynamic than not having one at all, and it's much more aero than putting it on the downtube."

4) "Wearing gloves in a time trial will slow you down more than using a non-aero wheel."

Your helmet and race number matters more than your wheelset? Sounds like bike porn blasphamy.

What say you STers? Discuss amongst yourselves...
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [Iron Buckeye] [ In reply to ]
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1) "A non-aero helmet creates four times the drag of a non-aero wheelset. So you can spend $2000 on a wheelset, or spend $200 on a helmet and be faster."

Rappstar and I have both said this numerous times on this forum.

2) "How you put your race number on matters more than having an aero wheel."

The way I've seen people pin them on, no s**t.

3) "On a round-tubed frame, having a bottle on your seat tube is more aerodynamic than not having one at all, and it's much more aero than putting it on the downtube."

There are so many possible interactions between different frame and bottle types, I'm not sure this statement is useful. In any case, the effects are probably very different over different yaws. Witness John Cobb's flip-flopping on this. Does anyone who cares about aero ride a round tube frame anyhow?

4) "Wearing gloves in a time trial will slow you down more than using a non-aero wheel."

You mean these gloves: http://www.2spi.com/...upp/cryo-gloves.html ?



-jens

My latest book: "Out of the Melting Pot, Into the Fire" is on sale on Amazon and at other online and local booksellers
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [Iron Buckeye] [ In reply to ]
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Yeah, well, I train all the time with a 2006 Texas State TTT champ who is a 'rocket scientist.' His secrets to success seem to be (start taking notes):

- racing a really old, heavy bike with non-aero wheels
- eating pasta (with chili) every damn night
- living without air conditioning (or heat)
- being crazy skinny

Hope that helps y'all...
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [Iron Buckeye] [ In reply to ]
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2) "How you put your race number on matters more than having an aero wheel."

Right side up is slower than upside down? Don't understand this comment. How are you supposed to wear your race number?
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [cerveloguy] [ In reply to ]
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I believe they are referring to how you put your race number ON YOUR BIKE, not on YOU.

Do you hang it just behind the headset, or just in front of your seat? Do you put it on the seat tube - below or above? I've seen quite a few folks cut the number enough that it wraps around a tube - you can still see the number, but it won't be flapping in the wind, etc.

How much stock do the MIT guys own in companies that make aero-helmets? Ha ha!

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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [NamssoB] [ In reply to ]
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since these guys are talking about bike racing I amost guarantee they are talking about how you put it on you, not the bike. Gluing the number to your jersey, crumpling it up, etc. all do better thing than pinning it at 4 corners and creating a nice little parachute on your jersey.
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [don] [ In reply to ]
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That makes a lot of sense. I believe it was a comment made by Lance a year or two ago as to where he wears it. I believe he had it further down his back closer to his butt rather than up top where he had a slight hump in his back projecting into the wind. I believe he aslo said to crumple it up before putting it on so it created less drag.
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [don] [ In reply to ]
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Yeah, they mentioned having the number glued on their jersey.
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [Iron Buckeye] [ In reply to ]
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I haven't found the Bicycling article, but here's one from the Boston Globe:

http://www.boston.com/news/globe/health_science/articles/2006/04/10/figuring_ways_to_go_faster_with_the_flow/

I would suggest the guy in the picture wear something other than jeans in the wind tunnel, but what would I know.

__________
there was no one chasing us... distance is its own reward.
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [Iron Buckeye] [ In reply to ]
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4) "Wearing gloves in a time trial will slow you down more than using a non-aero wheel."

Uh . . . what? Is that like saying that a hooded parka is not a good aero choice for a TT?








"People think it must be fun to be a super genius, but they don't realize how hard it is to put up with all the idiots in the world."
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [jens] [ In reply to ]
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The gloves tip is the one I find hard to believe. BUT, my guess is that it might be true at 0deg yaw. Without knowing what sort of yaw angles they were talking about, it's tough to take this stuff as gospel truth. Aero wheels, of course, are most beneficial at higher yaw angles, so at a 0deg case, I can see that some other things might make a difference.

Besides that, who cares about the aerodynamics of bottles on a ROUND tubed frame?

The helmet tip is a good one. Although, personally, I'm always very happy to show up to a race and see lots of my competitors wearing a road helmet! :)

"Non est ad astra mollis e terris via." - Seneca | rappstar.com | FB - Rappstar Racing | IG - @jordanrapp
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [Iron Buckeye] [ In reply to ]
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Am I the only one who finds it a bit early for the September issue of a magazine to be available?
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [Iron Buckeye] [ In reply to ]
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[reply]
1) "A non-aero helmet creates four times the drag of a non-aero wheelset. So you can spend $2000 on a wheelset, or spend $200 on a helmet and be faster."
[/reply]

not in my experience - aero wheels make me 1-2min faster over 15miles, the LG Prologue helmet (no visor) gets about 20-30sec.

People keep saying this about helmets vs wheels, but no-one has published any data.. until there is data from a couple of different tests, it's mere hearsay and anecdote..

"It is a good feeling for old men who have begun to fear failure, any sort of failure, to set a schedule for exercise and stick to it. If an aging man can run a distance of three miles, for instance, he knows that whatever his other failures may be, he is not completely wasted away." Romain Gary, SI interview
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [Iron Buckeye] [ In reply to ]
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Speaking of aerodynamics, does anyone know why a lot of the TTers don't wear sun glasses? Does it have to do with aerodynamics? It seems odd to me that they take them off for the time trial, especially when they still face the wind, bugs, etc...
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [doug in co] [ In reply to ]
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In Reply To:
not in my experience - aero wheels make me 1-2min faster over 15miles, the LG Prologue helmet (no visor) gets about 20-30sec.

People keep saying this about helmets vs wheels, but no-one has published any data.. until there is data from a couple of different tests, it's mere hearsay and anecdote..


I have before and i'll do it again. From my run at the LSWT (formerly Allied Aerospace) in San Diego:

CdA with LG Chrono helmet: .2343

CdA with LG Rocket & visor: .2172

At TT speeds, that equates to more than 15 watts. And that's just the diff. between two *aero* helmets.



- jens

My latest book: "Out of the Melting Pot, Into the Fire" is on sale on Amazon and at other online and local booksellers
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [samyers] [ In reply to ]
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Hard to believe why some don't wear sun glasses. Just about any pair of shades out there will be better than your eye sockets as far as aerodynamics I would think.
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [Bob Loblaw] [ In reply to ]
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Not really. A lot of pubs do a combined June/July or July/Aug issue so that their staff has some extra vacation in the summer. However their editorial schedule is set up, it probably pushes the September issue out a little early to let the staff take some vacation over the summer. Or, it's in an effort to not get behind over the late-fall/early-winter holidays.

The content of magazines, particularly features, is written WAY in advance of publication.
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [jens] [ In reply to ]
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Jens,

Any idea of the difference between the Chrono (which is obviously a bit less aero than the Rocket, at least when paired w/ a visor) and a regular road helmet?

Or, the difference (if any) for the Rocket with and without the visor?

Aero be damned, I don't think I could run a helmet w/ visor for a HIM or IM, I get too damn hot and sweaty as it is without them :-p I even end up taking off my sunglasses when climbing so my eyes can cool off.

As somebody else mentioned, there were a TON of aero helmets at LP this year.


float , hammer , and jog

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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [Murphy'sLaw] [ In reply to ]
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In Reply To:
Jens,

Any idea of the difference between the Chrono (which is obviously a bit less aero than the Rocket, at least when paired w/ a visor) and a regular road helmet?

Or, the difference (if any) for the Rocket with and without the visor?

Aero be damned, I don't think I could run a helmet w/ visor for a HIM or IM, I get too damn hot and sweaty as it is without them :-p I even end up taking off my sunglasses when climbing so my eyes can cool off.

As somebody else mentioned, there were a TON of aero helmets at LP this year.


From field tests and races, it looks like the visor doesn't make much of a difference.



-jens

My latest book: "Out of the Melting Pot, Into the Fire" is on sale on Amazon and at other online and local booksellers
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [beatnic_tx] [ In reply to ]
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[reply]Hard to believe why some don't wear sun glasses. Just about any pair of shades out there will be better than your eye sockets as far as aerodynamics I would think.[/reply]

I would have thought so too, but then why don't they wear them? These are cyclists who normally do. I also noticed one of the aero-helmets had the visor built in, which lead to my thoughts that maybe it had something to do with aerodynamics...

Does anyone know definitively?
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [samyers] [ In reply to ]
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<<Does anyone know definitively? >>

I know why I don't wear sunglasses in a TT. In the aero position, the top of the glasses frame is in my direct line of sight. I've tried glasses without a frame on top and found out that the frame does a very good job of guiding my sweat away from the lens. On frameless models, I just sweat down the lens and can't see a damn thing.

So, the short version is I don't wear glasses when I TT so I can see where I'm going.
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [jens] [ In reply to ]
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Jens,
Do you have CdA for a regular (non-aero) helmet also? I'm curious to see the difference.
Thanks.
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [Iron Buckeye] [ In reply to ]
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Rappstar is spot on, and this is something I've talked with Kim and Mark at MIT about before, you have to be very explicit when saying things to the media, as they love to lay it out there as a universal truth, when in most instances (like this one) it is only true for very finite conditions. The thing that they fail to say here is that this is all true, and very exciting, at zero degrees of yaw, but with increasing yaw angle the difference between aero and non aero wheels (same with non-aero and aero frames) becomes very big. At zero degrees the difference between a set of ksyriums and a 999 is maybe 10 watts, but at 15 degrees of yaw, it is roughly 60 watts. I also think that you have to be careful and specific when looking at things like the helmet issue. The helmet really needs to work with the body shape and also be worn in such a way that the tail lays down on the back for it to work ideally. We did nearly two entire days at the San Diego LSWT with Floyd, Botero and Perdiguero this February and found Floyd to be much faster with one particular helmet, Perdiguero slightly faster with another helmet altogether and Botero to be no different between them, although we made a fairing to modify one of them and saved nearly 25 grams of drag. They are spot on with the number placement, and the real advantage they have is putting each guy in the tunnel, there will be a place on everybody that the number is essentially invisible, but this is not exactly the same for everybody, but to put it on with double sided tape or similar, and get it pretty far back onto your butt will generally save some real time for most everybody.

But the real secret to speed that they need to be mentioning is that these guys spend lots of time in the tunnel tweaking each of them individually. Last time I was up there Mark Cote had his drag down to roughly 4 lbs! That is truly amazing, and is the result of dozens and dozens of hours in the tunnel refining everything from hand and body position to helmet and bike/wheel choice, and really exploiting the ability to determine what certain things work for each individual.

I haven't seen the article and don't know who all they are talking with, but last time I was up there setup that a couple of the guys were riding was the p3c with 999's so they clearly see some value in wheels and frames, but then if that were the point of the story it wouldn't be very shocking to anybody.

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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [Iron Buckeye] [ In reply to ]
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damn,,and i thought my Giro Aptos was the shit!
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Re: Bicycling Mag - Speed Secrets of Rocket Scientists? [Iron Buckeye] [ In reply to ]
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What do rocket scientists say about packing tape?
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