Aerodynamics / Aerodynamic Cost / Aero parts

I remember racing dead turn TTs back in Oz. :)

remember racing dead turn TTs back in Oz. :)

The colonies were always a bit behind :-) Even I'm not old enough to have done a dead turn in a RTTC open event, but we still had one on a club course back in the mid 80s.

No, we are just less risk-averse.

Yeah. My bikes fast.

Interesting piece by Tour.

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Trek and Felt beat Cervelo and five of them above the Venge?

They forgot the 'sponsored by Trek' message at the bottom...

Did they test a Precursa with a disc from the 90s?

Asking for a friend.

The black bars are results with same wheels so: Trek > Cervelo > Felt

Why the massive difference on the Cervelo with the wheels?

I think it's sold with low profile wheels, where the others all already have zipp 404-like aero wheels.

Cervelo are cheapskates... (or know that people will buy their own preferred wheels anyway)

So they're all tested with whatever they come with fitted? Presumably the same size and set for the same rider?

Yes I think that was it. The article was floating around somewhere. The venge is "slow" because there is 1000m elevation included in the comparison and it is a little heavier than the other bikes.

42s slower for 1000m in 100k? Hmm

I dont know if it matches up.

Person on weight weenies: New Venge and Madone both had 204 watts of drag but as soon as the road starts kicking up slightly the extra 866g the Venge has will have an impact.

866g could be 42s, no?

Unless I've fucked this up (which is entirely possible as I'm drinking in the office again)...
http://analyticcycling.com/ForcesLessWeight_Page.html

This Much Less Weight 0.866 kg
Over This Distance 100000 meters
On Hill of Slope 0.01 Decimal
Faster by 21.72 s
Ahead by 214.81 m
Frontal Area 0.5 m^2
Coefficient Wind Drag 0.5 Dimensionless
Air Density 1.226 kg/m^3
Weight Rider & Bike 75 kg
Rolling Coefficient 0.004 Dimensionless
Power 250 watts

So, in the realm of possibility but one tiny little adjustment could throw most of their figures out.
I mean, did they run the same saddle on all the bikes or just what it came with? Did they use the same pedals, same length cranks, same width bars, etc?

So, in the realm of possibility but one tiny little adjustment could throw most of their figures out.

yes... :)

Tulas.

Meh.

Just checked these out: non-stackable, which won't work with my diddy head tube.

R1 would, but £££ and a cursory search suggests I'd have more chance of finding some Ventus.

Positive rise stem, R1s aren't all that.

Double meh then.

A lot of it come down to clever spec.

Eg. The bikes with the best results come with aero shaped Road bars as standard.

This make a big difference.

I Think the Scott came out best for most roadies. It's stiff and can be built loads lighter. So it'd climb like a goat. Plus with the clever new bars from syncros, and some deep wheels it's plenty aero. So with a couple wheelsets you get a specialist climber and a specialist aero Road bike in one.

My argument for buying the felt was the ability to reverse the saddle and add clip ons for sleeveless mode.in my size the geometry becomes exactly that of the felt tri bikes.

My bike is more aero then any of those tested anyway. Cuz I haz the most aero skewers.

The bikes with the best results come with aero shaped Road bars as standard.

This make a big difference.

Lol, you can believe that if you want. The position of the rider will make roughly a billion times more difference.

This will be run (not by me) with a single ring, so the hanger and cable guide are superfluous.

Is it worth removing them?

I think it was @umop3pisdn who said Cervelo had found the hanger caused as much drag as the seat or down tube on one of their bikes.

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I am planning on drilling out the rivets on my front mech hangar on my exocet2 for that reason when my narrow wide 50t ring arrives.

If nothing else, it'll look tidier.

Just pop rivets, so easy enough to reinstate anyway.