*Tour Aero Bike Tests*
Moderator: robbosmans
Don't they test with two standard bottles already? I thought they did. And that's a good thing, I agree.
W/r/t bars, if it's a non-proprietary setup (including Cannondle, Spec, and Trek which allow for a standard stem without any modification) then they should use the same bars as a secondary measurement like the Zipp 404 test. Only bikes with truly proprietary bars wouldn't' benefit from this test. Wheels and bars are swapped by a lot of us.
If I want to go for an aero build. I want an aero frame, aero wheels, and aero cockpit. Testing different bikes with different components won't tell me which frame is aero.
A simple analogy is the same scenario for WW comparisons. Weighing complete bikes would make you think that the SuperSix is heavier than a Venge, but the difference comes from the pig of a SAVE cockpit which is easily changed.
W/r/t bars, if it's a non-proprietary setup (including Cannondle, Spec, and Trek which allow for a standard stem without any modification) then they should use the same bars as a secondary measurement like the Zipp 404 test. Only bikes with truly proprietary bars wouldn't' benefit from this test. Wheels and bars are swapped by a lot of us.
If I want to go for an aero build. I want an aero frame, aero wheels, and aero cockpit. Testing different bikes with different components won't tell me which frame is aero.
A simple analogy is the same scenario for WW comparisons. Weighing complete bikes would make you think that the SuperSix is heavier than a Venge, but the difference comes from the pig of a SAVE cockpit which is easily changed.
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It is easy to scale to speeds that you ride at. Power is proportional to velocity cubed so for 30 kph, you would be looking at a scaling factor of (30/45)^3 which is about 0.3. That means 20W at 45 kph would be 6W at 30 kph.rudye9mr wrote:Cool with it as is for a general guide.
i'm not averaging 45kmph in any case so use the results as a guide to effeciency...
in any event, so many small things can affect aero - loose clothing, cable out in the wind, one's own CdA etc.
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Could you explain me the reasoning behind this statement ?
My understanding is the following, if we consider two different drags at the same speed :
- Power from the rider to the cranks equals Torque x Rotation speed
- Considering the same rider cadency and the same development, any increase in drag translates to a proportional increase in torque in the cranks
- So, any increase in drag (let's say +10%) results in the same power increase for the rider
Now, if we extrapolate a drag value to another speed :
- Power approximately equals (rho/2).Cd.A.speed^2
- Any relative speed shift results in the squared value for power (+33% speed = +100% power, etc.)
So, to me, power is squared and drag is linear, but I may be missing something, thanks in advance !
The error is here - that's the expression for aerodynamic drag not for the power required to overcome it. So the drag is squared, and then P = F.v which is where you pick up the cubic v from.IanisCercariolo wrote: ↑Tue Nov 23, 2021 8:16 am- Power approximately equals (rho/2).Cd.A.speed^2
So, to me, power is squared and drag is linear, but I may be missing something, thanks in advance !
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Thanks !mgrl wrote: ↑Tue Nov 23, 2021 10:16 amThe error is here - that's the expression for aerodynamic drag not for the power required to overcome it. So the drag is squared, and then P = F.v which is where you pick up the cubic v from.IanisCercariolo wrote: ↑Tue Nov 23, 2021 8:16 am- Power approximately equals (rho/2).Cd.A.speed^2
So, to me, power is squared and drag is linear, but I may be missing something, thanks in advance !
Guys, do we have available some tests for
BMC Team machine SLR 01
Factor Ostro Vam
Scott Foil 2022
I am considering to build one of these bikes... (yes, i couldn't live without road bike for more than week)
BMC Team machine SLR 01
Factor Ostro Vam
Scott Foil 2022
I am considering to build one of these bikes... (yes, i couldn't live without road bike for more than week)
SW SL8 RTP 56cm @ 9270 / CLX II / CS OSPW / CEMA BB
S Epic 8 L @ XX T-Type / Berg Ratheberg 30 / Quarq / Fox Transfer SL 100mm / 3p
S Epic 8 L @ XX T-Type / Berg Ratheberg 30 / Quarq / Fox Transfer SL 100mm / 3p
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Which issue is that? Are these the only bikes tested?FlatlandClimber wrote: ↑Fri Jan 14, 2022 11:48 am
It may be the fastest bike, but man is the Storck ugly.
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Most recent issue 2/22 - these are the fastest bikes tested. Only 2 bikes they tested were Simplon and Storck in this issue.
Cervelo P5 Disc (2021) 9.1kg
Factor Ostro Gravel (2023) 8.0kg
S-Works SL8 (2023) 6.3kg
*weights are race ready, size 58/L.
Sold: Venge, S5 Disc, Roubaix Team, Open WI.DE, Émonda, Shiv TT, Crux, Aethos, SL7
Factor Ostro Gravel (2023) 8.0kg
S-Works SL8 (2023) 6.3kg
*weights are race ready, size 58/L.
Sold: Venge, S5 Disc, Roubaix Team, Open WI.DE, Émonda, Shiv TT, Crux, Aethos, SL7
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Would be keen to see results for Ostro VAM.
Or do you mean the One? Personally i think the Ostro is very close to the One aero wise, but a sh!t ton lighter.
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Interesting how a rebranded Pardus Spark EVO with a revised fork is among the world beaters in this testFlatlandClimber wrote: ↑Fri Jan 14, 2022 11:48 am
It may be the fastest bike, but man is the Storck ugly.
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