2022 PRO equipment thread

Questions about bike hire abroad and everything light bike related. No off-topic chat please

Moderators: robbosmans, Moderator Team


by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

www.starbike.com



Aeo
Posts: 444
Joined: Wed May 25, 2016 2:06 am

by Aeo

It was painful to watch Bardet ride the Foil in high mountain stages
Giant TCR Adv Pro Disc '17 · BH Lynx Race Evo '19 · Seraph GR029 '21 · Canyon Inflite AL '14

spartacus
Posts: 763
Joined: Mon Apr 04, 2011 6:53 pm

by spartacus

Why do people here think they know something pro teams, mechanics, and riders don't know?

A lot of the "information" these conclusions are based on remind me a lot of when I was a teenager and people added up all the horsepower they were going to get from their intake and cat back etc... except their car ended up being slower or the same lol.

spdntrxi
Posts: 4976
Joined: Sat Jul 20, 2013 6:11 pm

by spdntrxi

spartacus wrote:
Thu Aug 04, 2022 4:00 pm
TobinHatesYou wrote:
Wed Aug 03, 2022 9:49 pm
There’s no Kool-Aid. It’s been independently tested faster than an SL7. No amount of weight savings will make the SL7 faster on flat ground. Even >1kg of weight difference wouldn’t make the SL7 faster on a 5% grade.
Weight is literally not even relevant on flat ground since there's no gravitational acceleration. In theory anyway.
I could be wrong but THY is referring to aero in this statement. S5 vs SL7
2019 BMC TM01R
2002 Moots Compact-SL
2019 Parlee Z0XD
2020 Parlee TTiR

CarlosTheJackal
Posts: 32
Joined: Tue Oct 30, 2018 4:56 pm

by CarlosTheJackal

Does anyone actually believe the aero numbers that Cervelo and specialized put out? Staggeringly, it's pretty obvious that some have been drinking the Kool Aid.

TobinHatesYou
Posts: 10128
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

CarlosTheJackal wrote:
Sun Aug 07, 2022 10:59 am
Does anyone actually believe the aero numbers that Cervelo and specialized put out? Staggeringly, it's pretty obvious that some have been drinking the Kool Aid.
We’re not talking about first-party numbers. Seems some people have been drinking bleach.

CarlosTheJackal
Posts: 32
Joined: Tue Oct 30, 2018 4:56 pm

by CarlosTheJackal

TobinHatesYou wrote:
Mon Aug 08, 2022 1:59 am
CarlosTheJackal wrote:
Sun Aug 07, 2022 10:59 am
Does anyone actually believe the aero numbers that Cervelo and specialized put out? Staggeringly, it's pretty obvious that some have been drinking the Kool Aid.
We’re not talking about first-party numbers. Seems some people have been drinking bleach.
if you say so. :noidea:

spartacus
Posts: 763
Joined: Mon Apr 04, 2011 6:53 pm

by spartacus

The test numbers are valid and real... for a wind tunnel. Put the bikes in the real world with a rider on them, set up for the individual, with varying conditions, etc... all bets are off; the angle of your hoods or something small can exceed any theoretical wind tunnel difference between one reasonably comparable frame and the next.

But nobody wants to hear that because it's way easier to be like "all else being equal this is the fastest bike!" That's fine and all. I ride with enough fast people to know at the end of the day you just need a bike that's reasonably good and past that it's all rider. Sure marginal gains are a thing but unless you personally have been in a wind tunnel with your bike you're pissing in the wind and just deluding yourself about things.

User avatar
C36
Posts: 1696
Joined: Fri Mar 03, 2017 3:24 am

by C36

spartacus wrote:The test numbers are valid and real... for a wind tunnel. Put the bikes in the real world with a rider on them, set up for the individual, with varying conditions, etc... all bets are off; the angle of your hoods or something small can exceed any theoretical wind tunnel difference between one reasonably comparable frame and the next.

But nobody wants to hear that because it's way easier to be like "all else being equal this is the fastest bike!" That's fine and all. I ride with enough fast people to know at the end of the day you just need a bike that's reasonably good and past that it's all rider. Sure marginal gains are a thing but unless you personally have been in a wind tunnel with your bike you're pissing in the wind and just deluding yourself about things.
The absolute number is irrelevant because of the variable you mention. The deltas are what people should look.
Obviously a change on the bike will impact drag but this is a change that suits you you will carry it on all your bikes.

Lina
Posts: 520
Joined: Sat Sep 01, 2018 9:09 pm

by Lina

Your position on the bike should be pretty much the same regardless of the frame. That's why the rider position doesn't matter much in aero testing between frames and wheels. You can test on your own your position on the bike, and apply those changes to most frames. Of course if you're comparing two frames and one of them can't accommodate your position then of course that has an effect. But would you buy a frame that can't accommodate your position, regardless of how aero it is, in the first place?

blaugrana
Posts: 395
Joined: Wed May 24, 2017 9:49 pm

by blaugrana

C36 wrote:
Mon Aug 08, 2022 4:48 pm
spartacus wrote:The test numbers are valid and real... for a wind tunnel. Put the bikes in the real world with a rider on them, set up for the individual, with varying conditions, etc... all bets are off; the angle of your hoods or something small can exceed any theoretical wind tunnel difference between one reasonably comparable frame and the next.

But nobody wants to hear that because it's way easier to be like "all else being equal this is the fastest bike!" That's fine and all. I ride with enough fast people to know at the end of the day you just need a bike that's reasonably good and past that it's all rider. Sure marginal gains are a thing but unless you personally have been in a wind tunnel with your bike you're pissing in the wind and just deluding yourself about things.
The absolute number is irrelevant because of the variable you mention. The deltas are what people should look.
Obviously a change on the bike will impact drag but this is a change that suits you you will carry it on all your bikes.
The problem is that there is no guarantee that the deltas in watts carry over from the wind tunnel to the real world for any given rider on the two bikes you want to compare. You can't just add up the drag of the bike and the drag of the rider and call it a day, because both interact with each other, so if the difference between bikes is small, it could happen that bike A is faster than bike B on one rider, but bike B is faster than A on another.

CarlosTheJackal
Posts: 32
Joined: Tue Oct 30, 2018 4:56 pm

by CarlosTheJackal

^the above is a very good point but further up this thread, we have tobin and others relying on wind tunnel tests to quantify a difference that probably does not exist in the real world.

User avatar
C36
Posts: 1696
Joined: Fri Mar 03, 2017 3:24 am

by C36

blaugrana wrote: The problem is that there is no guarantee that the deltas in watts carry over from the wind tunnel to the real world for any given rider on the two bikes you want to compare. You can't just add up the drag of the bike and the drag of the rider and call it a day, because both interact with each other, so if the difference between bikes is small, it could happen that bike A is faster than bike B on one rider, but bike B is faster than A on another.
One known limitation is how performance translates into real-life turbulent conditions. Difficult to simulate, a way to assess them is starting at large yaw angles and then moving toward zero (you start with a detached flow) that I believe is now largely done by all serious brands for like 15 years.

From the test ran by pro-tour team I am aware of, there is no rider 1: A faster than B and then rider 2: B faster than A. Can some wheels generate bigger impact on frame A than B… as far as I know it always felt within the repeatability error… so not really.

Now one key part too often overlooked is the fitting. Comparing 2 frames without having this in mind is doing half of the research work.

TobinHatesYou
Posts: 10128
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

Are we trying to figure out if some riders’ big legs vs some riders’ stick legs generate different amounts of Venturi effect on different ST/seatpost shapes in transient/turbulent air at different yaw angles? Lol.

Post Reply