And before you know it, the thread just dies! :-)

Is that not just accessories from the tj tollakson collection?

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so some executive tweeted that the p5 is a BIGGER jump from the P4, than the P4 was from the P3.

Now, aero nerd that I am that makes me think - they dropped a higher % or amount of drag.

the p4 was around 17% less drag than the p3 per cervelo, or around 110 grams of drag less (depending on yaw angle)

So, lets place bets will the p5

1. Drop the drag from the p4 by MORE than 100 grams?

2. Or was his comment more about it being a big jump in terms of style, or engineering complexity, or some other such sillyness?

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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

20% increase in stiffness with BBright, 70 fewer grams of drag at low yaw and 100 grams drag at high yaw, is what I'm guessing.

I reckon a combination.

I for one will be stunned if they drop drag by more than 50 grams.

of course there will be the UCI and non UCI configurations to consider...

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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

Im getting all wet just thinking about getting my hands on a P5 now.
I wish Cervelo would confirm geometry so I could pre-order

I want to have the first one on my block :-)

Join the queue :)

Stunned if the frame drops 50 grams of drag, or the bike, or the bike with a rider, or the bike with a rider and stuff for an IM race, and at what yaw? Looking at the Day in the Tunnel article on ST my bet is Cervelo could legitimately make that claim one way or another without too much trouble. According to the Specialized engineer you could get close to that by cherry picking runs in the WT.

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Styrrell

lying about the data wouldn't actually change the drag of the p5 at all. I hope they don't lie about the data

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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 don't think they lie about data, but data has to be interpreted. look at the first graph in this article. http://www.slowtwitch.com/...the_Tunnel_1929.html

The Trek SC is about 100 grams less drag than the P4 at -13 degrees yaw. So if Cervelo just makes a direct copy of the SC then the claim of 100 grams better would be true, at least some of time.

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Styrrell

It will be interesting to see the drag numbers for the P5. Personally, I believe the P4 with a Ventus bar has the lowest drag at 0 yaw compared to the other "super" bikes. I would be very surprised if the P5 shows a 50 gram improvement. I would actually be very surprised if there is any improvement. My money is on the P5 showing the improvement over the P4 at other yaws.

In many places in the US during the summer there is very little wind. Especially early in the morning when most races take place. I think it is likely that the P4 would end up being a better choice in these conditions over the P5.

I would also not be surprised if the P4 ends up being the fastest option at 0 yaw for many, many years as the new bikes will be focusing on showing drag improvements over existing options and the most opportunity is not at 0.

It is too bad that they don't sell the existing P4 but with a nose cone.

I am really curious how you also compare a P4 to a P5 in the tunnel. I guess you take a P4 and add a bunch of spacers to compare it to an equivalent stack on a P5? Well this obviously would get you some improvement as you have exposed a round tube versus a more aero shape into the wind.

I I said the sky was blue

you would reply with "not at night"

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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

Only triathletes will state which bike they think will be better in certain conditions without really knowing anything about one of the two bikes.

nah, roadies are just as crazy.
they are just much stronger so you don't notice as much =)

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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

20% more exaggeration of how fast it is.

No but if you said the sky is always blue I would dispute it. Seeing as this discussion was about definable numbers and I was the only one who presented any I guess I don't see your issue.

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Styrrell

Please define "definable". I find your usage of the word disputable.

Please define "definable". I find your usage of the word disputable.

Jack gave numbers below and has speculated that its highly unlikely that a bike can be improved by those numbers

"the p4 was around 17% less drag than the p3 per cervelo, or around 110 grams of drag less (depending on yaw angle)

So, lets place bets will the p5

1. Drop the drag from the p4 by MORE than 100 grams?"

I just responded that at least one bike already exists that are "that much faster" at certain yaws. Its disputable if the P5 will be 100 gms faster, but he supplied the definition.

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Styrrell

100g would be nice, thank you very much.

I bet its the nose cone version only though...and only above 10 degrees of yaw.
I doubt that Cervelo would release a bike that is slower than an existing design at 0 yaw, so I also think that the P5 would at least match the P4 at 0 yaw.

So P4 performance at 0 yaw and as good as the best of the rest at yaw.

Win/win!

Does anyone else think its cool we haven't even seen a picture of this bike yet? Kind of hard to get people excited about a bike without a picture, so instead Cervelo engineers tweet about how much faster the P5 is over the P4...blah blah blah. It would be cool the day we actually see an unbiased wind tunnel test...however, it seems like there are too many variables to actually do it fairly with all the top bikes. Until then we can just get excited about some biased Cervelo testing about how fast the P4 is and now speculation about how the P5 is going to be a lot faster than the P4. I'm over it and glad I just decided to buy a different bike.

no, it was NOT an engineer that said that.



those happen all the time


Thanks for keeping us posted on your frustration at being unable to parse through available evidence.

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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

So you bought a bike that is probably slower and possibly more expensive because of what exactly? An "unbiased" wind tunnel test that doesnt exist?

Reminds me of a friend of mine that slagged me when I bought my P3 because they are "everywhere" and that he wanted something "unique", so he went and bought a Scott Plasma (original aero brick, not the later sweet rides) "just to be different". So he bought a slower, more expensive bike "to be different". Nice :-)

I think the big "leap" anything they've done may in fact be credited to a decent paint job for once ;-)

OK, it WAS an executive according to someones prior post, whatever dude. What are you the forum police?



Right, unbiased wind tunnel tests happen all the time with all the top bikes included, I forgot I'm dumb you're smart. Show me some of these tests so I can be enlightened.


Last month I was planning on buying the new P5 because the bike shop was hyping it up, etc. I was merely describing my frustration of Cervelo not even releasing even a picture of the P5 and so I decided to buy a different bike bra instead of waiting around. Who knows when I would have my bike if I waited. No reason to get butt hurt.