Aerodynamics / Aerodynamic Cost / Aero parts

😀

Ok let me rephrase that:
Why not upgrade all the wheels to dt swiss new aero spokes. Same drag but the stiffness of a 2mm spoke instead of 1.5

Or have you tested that already :)

Same drag

Have you tested that? They have 20% more frontal area per spoke, and although there might be something to gain from the slightly higher fineness ratio, it's going to be offset by a loss due to greater wetted area. Only testing will reveal the net effect.

Text book says yes :) (and I am fishing for if aerocoach knows more...)

Text book

^{[citation needed]}

Mostly "Fluid dynamic drag" by Sighard F. Hoerner, approximation formula for drag of a 2d ellipse cylinder, I can try and find the page/section if you are interested.

if you are not trolling

I'm not. I mean, the question is moot since DT and Sapim seem to have discontinued their 3mm spokes (New Aero and CX), but I've always wondered whether you could get a worthwhile gain from using fewer, bigger spokes (as Campag did with the OG Shamal). There seems to be no general agreement about the dimensions of New Aeros, and they might not even have been the same size through time. I've seen major axis listed as anywhere from 3.0 to 3.3 and minor from 1.0 to 1.2, but the ones I have here are 3.6×0.9. That's a pretty big spread of possible fineness, from 2.5 worst case which is actually lower than CX-Rays to 4.0 for the ones in my hand. What they certainly aren't is elliptical, but at least they are not sharp-cornered rectangles like Mavic bladed spokes, more a sort of rounded-off lozenge like this:

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yes the dt new aero spokes I have bought have all been 1.1x3.3mm. and like you say very close to the shape of cx ray on this picture:

Windtunnel test of shaft drivetrain.

~8 seconds over 40km,

I wonder if a singlespeed/fixed drivetrain is about the same:

https://www.ceramicspeed.com/en/cycling/journal/aero-is-everything

Cool idea, especially with the claimed efficiency savings.
However, the risk of cheesegratering your legs is high, which I imagine is not great for aerodynamics...

May make a lot more sense on a TT bike such as the Shiv.

However, the risk of cheesegratering your legs is high, which I imagine is not great for aerodynamics...

In what ways are the risks of injury greater with this setup than with a conventional drivetrain?

They have a cover on the back in this case, but the front chainring is basically saw teeth, without the chain covering the teeth.

Have they worked out how to change gear on it yet?

I wonder if a singlespeed/fixed drivetrain is about the same:

I've seen suggestions of the order of 15W aero gain by switching from dérailleur gears to fixed. That's going to be a lot more than 8s in a 25.
Which crank was on the dérailleur bike? Zipp claimed 9s for Vumacrono with both chain rings over common "non-aero" cranks, and @specialist says that was a rare example of understatement. Maybe Ceramicspeed got 20s from the crank then threw 12s away with their ridiculous gearbox 🙂

the claimed efficiency savings.

The claimed mechanical efficiency saving is just that - a claim. I don't think it will ever be realised, even in the unlikely event that they can make the product in the theoretically correct way and they are right about the hypothetical benefit over ordinary roller chain.
I have serious doubts about their maths - while the rolling element pinion might be efficient, they also need to calculate the large radial loads on the shaft bearings and the axial loading of the BB and hub bearings, both of which are also applied a long way off centre so they have significant shaft skewing moments to consider too.

But, hey, if it gets Ceramicspeed into people's media feeds, who cares if the drive train is bullshit as long as people keep buying the massively marked up and dubiously beneficial ceramic cartridge bearings?

Next step, sponsor top Ironman athlete, wait for them to win, use it as validation for the drivechain, and sell Ceramicspeed stuff to everyone.

Which crank was on the dérailleur bike?

Only says standard for Specialized venge 53-13, so I guess this s-work fact:

GCN video on custom narrow handlebars.
Bars look horrendous, aero position on the road bike looks really fast though.

Link?

Great if you don't need to steer, brake and only need pinkie- actuated eTap gear changing.

Time trialling thread >>>>

https://www.youtube.com/watch?v=AGil15gHDEk

Isn't there a minimum handlebar width UCI rule though? Definitely wouldn't want to ride near him in the bunch. I wonder how many watts he's saving

I think there is for TT base bars but not drop bars?

There's a CTT rule for sure. UCI check:

https://www.uci.org/docs/default-source/rules-and-regulations/1-gen-20190715-e.pdf?sfvrsn=b6f5c2e4_112