Is it possible to grab the integrated bottle on the P4 while still pedaling - and for that matter, but it back, while still pedaling?

Yes, I have ridden the bike now and removed and replaced the bottle with no problem whatsoever, even while steering in a tight parking lot. Think: Profile Razor aero bottle. Same thing.

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Tom Demerly
The Tri Shop.com

exactly

I have a power point presentation (from Look France) that i'm trying to convert for the masses. It outlines the steps they took to design what they feel is a top level Tri/TT frame. There is plenty of empirical data so hopefully I can get this going soo.

Essentially the rear end was designed so that as air travels past the front wheel, fork and seat tube into the rear wheel the gap does 2 things:

1. allows the air to transfer from airfoil a (seattube) to airfoil b (deep dish or disc wheel)
2. The gap allows for air travelling back towards the frame (when a wheel is rotating the top of the wheel is dragging air withit towards the seat and seatube area, while the lower part of the wheel is pushing it away past the rear der) to flow quickly and easily without turbulence created by a narrow space between the tire/wheel and the seatube. When Look tested their front end frame design (yes they did a bike virtually the exact same gap as a cervelo along with others) they found they needed a gap to allow air to continue flowing through the frame (front to back) but also not causing turbulence when air re enters the top portion of the seatube/brake area.

Remember the front end of the Look bikes (track 496, track 596, tri 596, TT 596) all have a proprietary headset and fork integration with somewhere close to 15 patents. This front end is what keeps the bike extremely stable under adverse conditions but also makes it one of the best handling Track/Tri/TT bikes in the world, something that is very very often overlooked by many brands. Take a look at the integration of the front end of a Look compared to other regular headtube designs, you'll see that our integrated front end allows for the rider to be lower and more aerodynamic in their tuck (which really translates to the best way to reduce overall watts used to acheive a certain speed ie: 40km/h) and being that much closer will give you much better handling at high speeds (look at a mountain bike and you'll see the shorter top tubes and stem lengths, especially with downhill mountain bikes)

I hope this helps

Thanks for the info and I'd love to see the powerpoint when you get it finished.

I'm impatiently waiting for my bike to be delivered. I'm sure I'll love the bike, all the new engineering that went into this frame will make it faster then my current Zipp 2001. The 2001 may be very fast in the tunnel, but with all the new stuff on the Look, from the front end to the crankset to the weight, I have no doubt that it'll be faster.

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Paul

That was excellent information. Thanks for sharing that.

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Tom Demerly
The Tri Shop.com

I ride a 56cm P2C and according to everything I can tell, i would need the largest size in the Look. So, no, you're not imagining things, I've noticed it too.

Bob

One of the features of the Look frames is their sizing is named oddly. I ride an "Extra Small" Look 596. I have both a small and extra small right now and the small is too large- too long and too high. It is simply too much bike. By comparison I am on a 54cm Cervelo Soloist Carbon SL and a 51cm P3C. I am 5'9" solid.

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Tom Demerly
The Tri Shop.com

I'm 5'11 or so and based off of the TT measurement and HT length, it seems the L is my size..But, as I have said, the geometry diagram on the Look website leave much to be desired. Have they ever considered labels?

I am using the rear hole (That sounds odd) on my P2C seat post due to hamstring injuries over the years and the TT measures over 57 CM. On the Look Large it's 56 or so.

I have a 58cm Look 585 and it fits like a glove.

Bob

The geometry chart Look published on the bike is.... difficult to interpret shall we say politely. Hopefully Slowman can do some easy stack and reach on it for a more meaningful comparison. I originally was certain I'd be on the small. When the demo bike arrived it was very large. I was briefly thinking it was mislabelled.

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Tom Demerly
The Tri Shop.com

Here is a short explanation of the 596 from Ming at LookUSA

http://reviews.roadbikereview.com/...first-look-look-596/

That was an excellent little synopsis that explained Look's idea behind the wheel gap particularly well. Thank you for finding that. Useful.

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Tom Demerly
The Tri Shop.com

Above is an image taken while using the wind tunnel when the rear end of a more traditional shaped Tri bike, as you can see here there is increased turbulence as the air coming back around the wheel towards the seatube has a very small window in which to enter, this causes air flow turbulence and therefore slowing the riders down because they need to put in more energy to turn the rear wheel.



Above is what Look finally decided on after many many different rear ends (changing the seatube angle, airfoil, etc), as you can see by inserting the cutouts by the seatstays (yes there are cut outs in the stays and in the front fork to allow air to flow through better, take a look next time you're in a store) and increasing the width of the gap between the seatube and wheel there is significantly less turbulence and hence less energy (watts) is needed to move the bike forward, which simply put turns into a faster bike.


Remember when looking at this engineering imaging air is traveling in two directions.
1. The wind/resistence we create when riding comes from the front of the bike and travels to the back, we use airfoil desing tubes, fork, headtube, wheels etc to try and minimize this.
2. The wind created by the wheel when it rotates, this is called the Wheels Viscosity effect. Where the top half of the wheel is bring air back against the bike from back to front into three areas of the frame: the fork, seat stays and seatube areas.

That is why Look feels their design is unique because they have mitigated this Viscosity effect with cutouts and extra spacing at both the front fork area and the seat stay/seatube.

Excellent resource. Say, can I borrow these images for use in our review?

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Tom Demerly
The Tri Shop.com

absolutely, that is exactly what they were intended for!

If the P4 had been designed by any bike manufacturer other than Cervelo, it would have been laughed out of existence IMO. I don't care what the tunnel tests would have claimed. Is that some sort of Benito box down there?

With all due respect and haven't read the entire thread...

That is not an image of a wind tunnel... that is a screen shot of a CFD application.

And as with any data and without more information about the assumptions in the model, it means little since GIGO.

g

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greg
www.wattagetraining.com

 
furthermore..
looking through the guy's bikes at kona thread (http://picasaweb.google.com/ben2008kona/GuysBikes#) it seems to me that a huge impact will be made on the turbulance at the rear based on their number plate placement..

ie..

It is kind of funny that you mention that since the bike companies spend huge amounts of time in the wind tunnel and doing computer modeling of their bike to minimize the drag and then we slap our numbers all over the bike. I wonder if there have been any aerodynamic studies on where the best location is for a number plate?

Not to mention, the drag created by the numbers flapping away on number belts (as can be seen in the same pictures).

Just out of curiosity, why do we hold some manfacturers to one standard of technical proof while holding other manufacturers to a completely different one?

Look says it has something intriguing, but if they don't post video, computer print outs, and swear on their first born child that it's true, most on ST call them liars, cast doubt, or simply cut them down. Yesteday Rappstar dismissed in hand their statements about the wheel gap simply because a word was missing from a translated piece of marketing material. C'mon that pretty juvenile. If you did some digging (Um, hello Google) you can find the video on Road Bike Review, which explains their thought on the wheel gap. But, again, one standard of proof and an immediate dismission of statements.

On the other hand, when Cervelo introduced the P4 and said it was 20% faster than the P3, everyone in the world took them on their word. Glitzy marketing material and fake subterfuge aside, Cervelo showed didly pooh the the public at launch but we took them at their word. Have they shown a wind tunnel video yet? Have they shown their data? Have they shown anything more than marketing materials? Have they shown anything that we're requiring Look to present? Not to my knowledge. At some point Cervelo will say "This frame is so efficient it propels itself and also levitates" and we'll take them at their word.

And don't think I am a Cervelo hater, I have two right now.

Bob

Since the stem is so adjustable doesn't that make determining the stack and reach virtually impossible? Jordan Rapp implied that in response to a question I sent him that I posted in another thread. I will repost here for those only following this thread.

This is what Jordan Rapp wrote me back (posted with his permission) when I asked him about the concerns he mentioned about the Look 596 in his Interbike review regarding how steep the bike was designed to be ridden:

We are in the midst of it. They are working with me to come up with good answers. The more we talk, the more I see the additional complications, since where the stem fixes effectively changes both the stack and reach of each bike since, obviously, the headtube is angled. Using the front-center//offset//HTA I've deduced that the bike is actually probably designed to be ridden steeper than LOOK might believe. I think the bike is probably most comparable to a Felt DA in terms of geometry, with the L LOOK matching up pretty with the 56 DA. The biggest LOOK is still a relatively small bike, which LOOK actually indicates calling the biggest size an L (55), which would make sense given that I don't know of any TdF riders that ride much bigger than that size for TT bikes; Cancellara, for example, rides a 56 P3C, and he is one of the bigger riders in the Tour.
Bottom line, though, is that the 596 is probably more of steep bike than LOOK pitches, and maybe even moreso than they actually recognize themselves.

Are there any images like this for the front fork?

I'm sure Look was referring to windtunnels in Europe. Are any of the windtunnels you mentioned in Europe? So please get off of your high horse, and quit bashing other bike companies. Afterall, your P4 is the ugliest bike that I have ever seen.

I am not holding anyone to some high standard.

The poster I replied to showed a picture of "an apple" and called it "an orange".

I merely pointed out that the picture was in fact, "an apple".

What conclusions that one can make about the above facts and what that means for the validity of the bike or poster in question are yours to make.

CFD is a tool (and a good one at that), but is only as good as the information given it to process (the assumptions). Hence the GIGO* statement. You must remember it was with CFD that it was "proven" that bees and hummingbirds were incapable of flight, again GIGO.

Typically the process goes something like this:design something, test it in CFD, modify design until it is the best or close to optimized in CFD, verify tests in tunnel (which should match CFD analysis if the assumptions are in fact correct), repeat as necessary to achieve goal(s).

Ancedotally, the bike in question (the look) I was more impressed with in person at interbike than what I had seen here and elsewhere online.

g

*GIGO = Garbage In, Garbage Out which simply means if you give a model (however accurate or inaccurate) bad information, it will give you bad results.

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greg
www.wattagetraining.com

As Greg pointed out...this is NOT a wind tunnel pic, it's a screenshot from a CFD simulation. As someone who deals with similar simulations fairly often, let me just say that initial assumptions and boundary condition selections mean EVERYTHING...or as Greg put it, GIGO.

Anyway...looking at that top pic, I'm not convinced that the turbulence shown is a function of the gap and air being dragged forward so much as it is flow separation caused by a poorly shaped seatstay/seattube junction...

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http://bikeblather.blogspot.com/