I'm still waiting for the independent data that proves cervelo is faster than the Transition, DA, or any other frame.

I think the real world difference would be a lot smaller than people think, if indeed there is one at all.

Independent data? Where would that come from? Who would pay for it? That doesn't seem likely, whether to prove or disprove Cervelo's (or any other brand's) claims.[/reply]

Edited because I read that you later got my point before I finished reading the thread...

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"Lemond is cycling's version of Rev Jessie Jackson." -johnnyperu 5/18/07
"Just because I suck doesn't mean my bike has to" -rickn 9/2/08

Triathlete mag could do it. Just need the bikes and tunnel time.

But fair enough, independent data might be a pipe dream...how about ANY comparable data? So far we have numbers from Cervelo, and just assume that they're the fastest right? (the assumption being that specialized and felt don't release theirs because they're scared, right?)

I just have trouble believing that the real world difference between a P4 and a transition is significant. It probably boils down to who has the best fork design.

I do agree with you, BUT I kind of like the way the P4 looks....

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"Lemond is cycling's version of Rev Jessie Jackson." -johnnyperu 5/18/07
"Just because I suck doesn't mean my bike has to" -rickn 9/2/08

I am so sick of this idiotic concept. A person on an aero bike at 20mph saves more TOTAL TIME on a specific course than a person riding 30mph. THIS IS INDISPUTABLE FACT. I posted this in the P4 thread just yesterday:

CdA starting point 0.25 (reasonably decent but not great), Crr 0.007 (typical from my field testing with decent tires on medium-to-decent roads). Saving 10% in CdA gives us a new number of 0.225 (pretty good number). Here's the two cases over 56 miles:
CdA 0.25 = 20mph: 2.8 hours, 159.2W
CdA 0.225 = 20.62 mph: 2.716hrs, 159.2W, total time saved 5mins 2secs. Total percent saved 3.09%

CdA 0.25 = 30mph: 1.867hrs, 444.1W
CdA 0.225 = 31mph: 1.806hrs, 444.1W total time saved 3mins 40secs. Total percent saved 3.38%

So that's REALITY. So stop arguing, get out a spreadsheet and calculate it yourself if you don't believe me. Ugh.

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So from your postings above, it would seem they definitely beat you because they had better equipment. How many did you beat at Nationals just because you're a better rider?

Um ... I don't believe I said that at all. Here's something I posted on another thread this morning (a thread asking if "aero stuff" is all hype):

I was at the Masters National Time Trial Championships this year on my P3C with a Zipp 808 on the front and a Zipp Sub-9 on the rear. Pretty much state-of-the-art stuff.

The guy who won my age group handed me my ass on a platter. He was riding a 2004 vintage (or thereabouts) aluminum P3. He had some decent race wheels, but certainly not the latest and greatest. What he had that he would probably tell you made the most difference was a power meter and one of the best coaches/trainers in the business (Max Testa). (It probably didn't hurt, either, that he had femurs that appeared to go from his ankles to his neck. ;-) )

The relative importance of an "aero" bike versus a round-tube standard road bike ... significant.

The relative difference between "aero" bikes ... not very significant.

The biggest difference comes from getting the body into the aero position. It's the body that's responsible for most of the drag.

I've been racing the P3C for 18 months now and I still haven't beat the times I did previously on my P3sl. But I'm not getting any younger, either.

I beat 26 riders at Nationals. Did I beat them because I'm a better rider? Define better. Was I stronger? Did I produce more watts? Probably more than some. Maybe I was smarter than others and got more out of my watts by being more aero. I've got a photo from Nationals where I'm passing a guy just before the finish line. He's sitting up like a dang drag chute on one of the fastest sections of the course where the thing to do was to get low and go.
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Bob C.

The "science" on any matter can never be settled until every possible variable is taken into account.

I finally realized what strikes me about the P4 and why I like it.

It's an engineer's bike. Black Paint white plain letters. That is the "style" of an engineer that says, "This is the fastest bike, we don't need marketing, cool graphics, or a Pro tour team to sell this: it's performance is the only selling point." I question people that call Cervelo a "marketing" company. They are an engineering company.

If you visual appeal is more important than performance, get the P3C and save some money.

In college we would paint all of our wind tunnel models flat black. There was a technical reason to do this: smoke and tufts show up better white on black, but after the testing was completed we always painted them a gloss black. It was simple and always looked "mean".

it's actually a simple difference Andy....

1. There are the "engineer" types of the world, and
2. There are the "artist" types of the world.
3. There is some subset consisting of both.

I can say that many times (in fact - most of the time), those two groups do NOT go hand-in-hand :-) This is why red, black, yellow, and royal blue are a mainstay of color choices in the triathlon world (typically even more oriented towards #1 above), and then you have the unique paint jobs of many of the euro bikes (who appeal to a wider spectrum of the senses and audience #2 - specifically the Italians who have always been passionate about the emotional connectivity with their bikes).

Additionally, you'll have a large disconnect between those who COULD place/win in their races, and those who can't (the vast majority). Those who can't will like to have something that makes them faster, but they have to feel good about their purchase, and thus want something they enjoy looking at when they ride it. It is similar to cars (I spend alot of time in my car and could never rationalize purchasing a "functional only" type vehicle if it aesthetically doesn't please me).

I'm guessing those people you don't seem to understand may be some of the "faster" people you associate with?


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Craig Preston - President / Preston Presentations
Saving the world with more professional, powerful, and persuasive presentations - one audience at a time.

OK, but I'm not even sure I think the round tubes make *that* much difference either. My best 40K ever was on a Panasonic DX2000 road frame converted to a TT bike with Syntace bullhorn bars and C2 clip ons. I raced it with Nimble Crosswinds and turned in a 56:56 (The marshall swears she didn't make up the number!) The fit was mostly done instinctively over that season, but I must have had a good position. That was in '99.

I'll believe an aero frame makes some difference since I traded in the Panasonic on a P2C, but I've still never beaten that time either. But comparatively speaking, the drag difference between the P3 and P2 has got to be tiny compared to the Panasonic and the difference of the P4 even smaller still.

Same as you, I'm getting older and I took a few years off. My best 40K time on the P2C is 58:31 with a wheelbuilder cover on the rear and still running a Nimble Crosswind on the front. (I can't afford that Zipp bling.)

I don't honestly believe the P3 or P4 would make me any faster on any given day. I do believe if I train my ass off, I might be able to break 56:00 next year.

I don't honestly believe the P3 or P4 would make me any faster on any given day. I do believe if I train my ass off, I might be able to break 56:00 next year.

What I've read that makes the most sense to me is that 95% of the equation is the rider -- power output and being in a good, aero position. The bike is the remaining 5%. So maybe if a P4 is a 20% improvement in aero drag than a P3C (and I'm not saying it is or isn't), maybe it's a 20% improvement on the 5% part of the equation that's represented by the bike ... or in other words, it's 1%.

If you can do a 40k TT at 30 mph (wind tunnel speed), that's 50 minutes. Guess how much a 1% improvement will save you? 30 seconds! (That's the claimed savings the P4 represents. Not saying I'm buying it. I'm just sayin' ...)

On another note, when I went to nationals this year, the thing I came away convinced of was that the people who were better than me were better predominantly because of more disciplined training ... and perhaps some superior physiology. I know I need a power meter and a coach more than I need a P4, but one sounds a whole lot more fun than the other. ;-)

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Bob C.

The "science" on any matter can never be settled until every possible variable is taken into account.

sorry I disagree, I will ride any bike and say all the nice things about it if I got to it for free. Of course, some conditions - such as a it being a top (or near top) of line modern racing bike!

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Simple Simon
Where's the Fried Chicken??

Your math is correct IF wind resistance was Lineal. Only problem -- it is NOT lineal.

Never mind -- your mind is made up and any facts about real world physics won't change it.

The power required to overcome the aerodynamic drag is given by:
Note that the power needed to push an object through a fluid increases as the cube of the velocity. A car cruising on a highway at 50 mph (80 km/h) may require only 10 horsepower (7.5 kW) to overcome air drag, but that same car at 100 mph (160 km/h) requires 80 hp (60 kW). With a doubling of speed the drag (force) quadruples per the formula. Exerting four times the force over a fixed distance produces four times as much work. At twice the speed the work (resulting in displacement over a fixed distance) is done twice as fast. Since power is the rate of doing work, four times the work done in half the time requires eight times the power.

Sorry, I am not gonna go down to your level of namecalling.
That is what the majority of decent people consider "without class"

Triathlon relays, he?
I still think my chances of you taking an ego-beating in an Half or full IM by a "classy guy" with a round tube bike are still pretty good.

Give me a call if you finally have that breakdown. Fixed a couple of your kind.

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Ego numquam pronuncio mendacium,
sed sum homo salvaticus

Chill out! Sheesh.