Why? Given the stack height of the new "super bikes" sounds like they are just following suit. Specialized, Trek, Scott, all have taller stacks than the P4.

Where is the wind tunnel data that says you guys have to have your faces closer to the front wheel?

The all new Cervelo P5. Geometry so aggressive, you can lick the front tire!

This is not a bad question. It seems like having your head down and out of the wind would be faster... but is there any data out there? Has anyone measured their drag at various levels of drop?

Lots of people lots of times. In a nutshell having your head not sticking up is good, as long as it doesn't effect power much. Its possible to go too low but thats much less common.

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Styrrell

This is not a bad question. It seems like having your head down and out of the wind would be faster... but is there any data out there? Has anyone measured their drag at various levels of drop?[/quote]
Yes, at LSWT

Easier geometry means opening the geom. up to as many buyers as possible either by nailing a better average fit or buy making the fit more flexible and adjustable . I believe the 'easy' can be apportioned to it being easier on their bottom line.

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https://www.pbandjcoaching.com
https://www.thisbigroadtrip.com

Maybe not with the P5, but I think we will see that kind of jump again. Just give it some time.

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Advanced Aero TopTube Storage for Road, Gravel, & Tri...ZeroSlip & Direct-mount, made in the USA.
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Agree. My fear is they are taking the same route Specialized did with the new shiv. Lot's of stack. Hoping I am wrong as I have been waiting for this bike for a long time.

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http://www.frostyjunction.com/
https://twitter.com/FrostyJunction

Sounds like increased stack http://triathlon.competitor.com/...oon-cervelo-p5_44617

any idea of the consequences associated with having your bars at like the middle of the head tube? I have a -30 deg stem on my p3 already !

I somehow remember someone (i think jens) saying that he found that spacers didn't significantly affect drag, only able to tell the difference when modifying the torso's angle of attack wrt the wind.

the reason I think not is there isn't much difference between a p4 with disc rear firecrest front, aero front brake, and no bike at all =)

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

perhaps there will be a low stack and high stack model. like the p3/p2 are (in some sizes)

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

I agree, but my guess is it'll have to be some wild beam style bike a-la the ZIPP or softride frames. I'm guessing they're maxing out the double diamond frame given the rules they currently operate with.

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Ignorance is bliss until they take your bliss away.

I'm not certain the softride design tested faster than a P3

Yes, I've established from field testing on several different occasions that there is an optimal level of drop for me, and going lower increases my drag. It's quite easy to see why in a picture from the side, because my upper back just ends up facing the wind when I take my shoulders down too low. Once your shoulders are lower than your hips, you're in danger of being too low, IMO. I'd need something like 8cm of spacers on a P4 to achieve my optimal position, so more stack might finally give me a chance of being able to make a Cervelo fit me. I'm currently on an SC and the full stack of aero spacers between base bar and pads is just enough to get me to my most aero position.

heres some perspective
a p3 with old zipp 808s on it is about 5 minutes of drag per 40k

a p4 with new 808s drops that by like 20%, so 4 minutes of drag per 40k

if the frame and wheels and components all were 0 drag you would only save 4 minutes per 40k

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

What a bunch of crap spewing that is. The P2 isn't that much less aggressive than a P4. The P2 is more aggressive than the Trek Speed Concept and way more than the Shiv.

right on the excel document sitting on my computer. i suspect others have it through golden cheetahs aerolab.

That is quite low. I don't even think Bjorn on his P3 and a negative stem ever got that low. Do you have a pic of yourself on the bike with that much drop? Would be fun to see as that is a crazy amount of drop. Also curious how you determined that you current position is optimal. 8 spacers is a lot of spacers.

Btw, I am not asking because I am looking to argue. I am simply just curious.

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http://www.frostyjunction.com/
https://twitter.com/FrostyJunction

Per STJay,

@ bikerumor.com

http://www.bikerumor.com/...p;utm_medium=twitter

Note that I didn't say my shoulders are as low as my hips, just that in general I find it hard to see how it's more aero once you get that low, even with a flat back. My back tends to curve quite a bit, so I have my upper back facing the wind before I get that low. This picture doesn't show it all that clearly, I'd have to do a lot of searching to find one from side on, but basically, my optimum position has the horizontal line bisecting the angles of the front and back of my torso. If I go up, the front generates more drag, and if I go down, the back generates more drag. I've found this to be my optimal position by doing field tests on several different occasions with the same result every time, nailed down to 1cm up or down being less aero:
http://www.onlinepictureproof.com/...264/?w=625&h=525

how's the fit with that smart skinsuit? nice set up

I'll bet you're REALLY tall and/or have long legs relative to your torso, huh?

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http://bikeblather.blogspot.com/

I've sold that suit now, I was never happy with the fit around the neck, you can see gaps in that photo. I never formally field tested it back to back against my PBK suit, but I had plenty of TT comparisons on the same course where the PBK gave me a lower aerolabbed CdA, and none where it ever worked out the other way round.


Yes, long legs short torso. So I'd need a small size Cervelo to get a short enough reach, but then the stack is crazy low for me.