Good job. Another nice and objective point to analyze our "aero" and so marketed frames around!
Marcos.

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http://www.marcosapenedoamaral.blogspot.com

What about the data regarding the new Giant tri line. The Trinity Alliance A0 and A1? Due to Dan Empfield, they are almost geometrically perfect as the article written here some time ago, right?! It would be nice to have those bikes on the chart as they might be a good selling tri bike this year.

Marcos

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http://www.marcosapenedoamaral.blogspot.com

I really like the geometry of the Alliances too but the importer here hasn't even heard of them. THe headtube and downtube appear quite bulbous from the pics I've seen but I'm interested in the prospect of a nice frame with great geometry at a good pricepoint.

I'm hoping to find a standard trinity to measure, might take my calipers to the Tri tomorrow morning (it's summer down here :-)

Here is the latest chart for those who, like me, find this stuff interesting. Pinarello Montello FP8 added (costs the same for a frame as a P3C bike) and Wiler Cento Crono - star of this article http://www.cyclingnews.com/...06/cunego_windtunnel - note where it sits on the chart. Having seen the awful tube shaping I wonder what John Cobb had to say about it...



I should probably sort so that the P3 is above the Dual, maybe in the next edition.
And the Avanti team Kona is the same frame as the Blue T12 but with different seatstays (Blues are deeper)

I have a custom TT bike - the tubeset is Project 96 Aero - whose dimensions are 30x80 mm.

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I race duathlons and like it.

3:1 is far from optimal for aerodynamics, it is just the maximum allowed by the UCI.

80mm is the max depth too.

Felt has made the B2 and DA frame 25mm wide wherever possible, and thus 75mm deep except in the cross section where the foot crosses the downtube, but I won't get too in depth as to why we switched from a straight leading edge here. We also used the Bayonet fork on the DA to increase the effective cross section (among other reasons) on the front of the bike. This frame is the closest execution to the edge of the UCI rules there is. Where the frame bulges to accept BBs, head tubes, etc. we increase the depth to the maximum 80mm. allowed.


It is a fun project to go through all the shapes and see how thourough it has been refined.



-SD

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https://www.kickstarter.com/...bike-for-the-new-era

hmmmm, my Hotta have 0 mm down tube cross section :-)
http://forums.roadbikereview.com/showthread.php?t=78142

Anyone thought of measuring the Tiphoon or Blade for comparison? I would be curious to see those.

-Steve

Any news about it?

Marcos.

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http://www.marcosapenedoamaral.blogspot.com

I found a Trinity whose owner let me measure it, there were a couple of other bikes there that I'd have liked to measure but didnt want to have to explain to the owner about my chart because then they would ask where their bike would sit and I would have to say "at the bottom" and that would be uncomfortable.

Trinity sits just below Kestrel Airfoil based on DT but should really be higher on the chart as it does well on other measurements like HT.

From what I could find out the Trinity Alliance is only coming out in the nrxt few weeks so unlikely that anyone has one

Thanks to John Cobb, my Hooker and I have recently been reunited, so I pulled out my el cheapo calipers to make some direct measurements rather than relying on my memory of the specifications:

Down tube: 68 x 22 mm
Seat tube: 68 x 22 mm
Seat post: 58 x 16 mm
Seat stays: 18 x 9 mm
Fork (at midpoint): 31 x 10 mm
Headtube: 35 mm

(Note: all dimensions are rounded to the nearest 1 mm, and may be slight overestimates as I was trying not to scratch the paint.)

Why did you part with her?

[reply]
Thanks to John Cobb, my Hooker and I have recently been reunited...


(Note: all dimensions are rounded to the nearest 1 mm, and may be slight overestimates as I was trying not to scratch the paint.)[/reply]

and in the same week, I parted with my two hookers...

makes me sad, but excited for the new rides.

and you wouldn't scratch it - it is powdercoat!!!

also of note in all this discussion is that it isn't the perpendicular profile that matters but the profile @ angle of attack (ie the profile in the horizontal plane)...

g

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greg
www.wattagetraining.com

I traded it for something that was 1) more user-friendly, and 2) UCI legal. Due to the latter issue I will probably never race the Hooker again, but it's still nice to have it back.

In my experience, the powdercoat paint on the Hookers is fairly easy to scratch - not down to bare metal, maybe, but enough to leave a mark.

I was going to say the same thing then I looked at the chart closer and noticed a horizontal major column which I presume is the major divided by the cos or sine of the DT angle (depending on how it's measured).

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Jonathan Blyer,
ACME Bicycle Co., Brooklyn, NY

I assumed that most dts have roughly the same angle of attack to derive the profile in horizontal plane. Haven't done it for ST as that angle varies more but is pretty close to vertical so not as important to recalc. Seatstay angles are all over the place so didn't do it there either

Thanks, I don't really expect to ever get close to one of those bikes so the gaps were going to remain in the chart. It's still at the top.

All my measurements are to the nearest mm as I hate scratching paint - especially when the store owner is standing watching what I'm doing and asking questions.

Any updates to this chart? The Felt DA/B2 and S22 are incomplete, no Giant Trinity, no P4 (oh the horror!), no Jamis and no updated 09 Kestrel Airfoil. I'm sure there are others missing as well.

It'd be nice if we could keep this up-to-date and accessible a la stack and reach tables. Anyone agree?

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In Reply To

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I really like the geometry of the Alliances too but the importer here hasn't even heard of them. THe headtube and downtube appear quite bulbous from the pics I've seen but I'm interested in the prospect of a nice frame with great geometry at a good pricepoint.

I'm hoping to find a standard trinity to measure, might take my calipers to the Tri tomorrow morning (it's summer down here :-)

Here is the latest chart for those who, like me, find this stuff interesting. Pinarello Montello FP8 added (costs the same for a frame as a P3C bike) and Wiler Cento Crono - star of this article http://www.cyclingnews.com/...06/cunego_windtunnel - note where it sits on the chart. Having seen the awful tube shaping I wonder what John Cobb had to say about it...



I should probably sort so that the P3 is above the Dual, maybe in the next edition.
And the Avanti team Kona is the same frame as the Blue T12 but with different seatstays (Blues are deeper)[/reply]