Aero test. Trek Madone, Venge, Cervleo S5, Giant Propel & Canyon Aeroad

Discuss light weight issues concerning road bikes & parts.
Post Reply
User Name
Posts: 596
Joined: Tue Jun 07, 2005 3:32 pm

by User Name

Indoor velodrome

..........................................Watts required at 45kph
Hand position: ........................Hoods......Drops.....Aero on Hoods

Trek Madone Race Shop Ltd...........301.6.....299.1.......279.1
Specialized S-Works Venge ViAS......301.6.....300.1.......286.1
Canyon Aeroad CF SLX.................307.6.....295.2.......281.5
Cervelo S5...............................309.2.....306.5.......281.1
Giant Propel Advanced SL.............343.0......332.6.......298.0

http://www.cyclingweekly.com/news/produ ... GYfV3zG.99

"Prior to each run, temperature, air pressure and system weight were recorded. A coefficient rolling resistance was measured and calculated. By subtracting the watts required to overcome drive train friction and rolling resistance, we are left with the aero watts – our comparative measure (the watts required to drag at 45kph).

These are presented for each bike for three different riding positions – the hoods, the drops and riding in a low aero position on the hoods. For consistency, the bikes were set up in as close a riding position to each other as possible and the same wheels were used in all the bikes. The reason for this is that we wanted the variable to be the bike frame itself and not the rider or wheelset.

The wheels were a set of Fast Forward F9Rs with a Power Tap G3 rear hub for power measurement. For reference, 1W equates to 0.1 second per kilometre, as a rule of thumb.

Limitations should also be pointed out – testing in an indoor velodrome has the advantage of good run repeatability and consistency. The main disadvantage is that wind yaw angles can be lower than those that can be experienced on the road, particularly when riding at slower speeds.

While every effort was made to get the bikes in the same riding position, the Canyon had a slight advantage with 41cm wide bar, while the others all had 42cm.

It should also be pointed out that slightly different handle bar shapes will undoubtedly create slight differences, hence the decision to test each bike in three positions. Coefficient of variance was very good lap to lap, of around 0.8-1.3 per cent across all test runs. Test velocity was typically 48kph (13.3m/s) and air density was 1.1663kg/m3."
Last edited by User Name on Tue Apr 25, 2017 1:19 pm, edited 1 time in total.

by Weenie


L3X
Posts: 277
Joined: Wed Feb 25, 2009 8:39 pm

by L3X

Read this as well, seems like they did what they could to control the environment.

Results wise it looks like there's no significant difference, maybe only for the Propel vs. other 4 on hoods/drops.

wingguy
Posts: 3527
Joined: Thu Mar 08, 2012 11:43 pm

by wingguy

There's something seriously hinky going on with those results.

The Canyon and Giant had 12 and 10 watt changes between hoods and drops, the others had 1.5 to 2.5 watt changes between those same positions. And that discrepancy is as big as the whole margin between the bikes, if you exclude the Propel.

It also asks us to believe that switching from riding a Madone to a Propel makes a 16 times greater aero difference than switching from the hoods to the drops on the Madone. Nope nope nope.

Shrike
Posts: 1071
Joined: Fri Jun 03, 2016 5:08 pm

by Shrike

The S5 has compact drops so that would explain the reason it did (comparatively) poorly to say the Aeroad which has deep drops. Makes perfect sense.

Interesting then that the drops on the S5, Madone and VIAS are pretty much useless. Lucky to save a watt or two. May as well chill on the hoods and save your back until you're ready to go aero hoods and go full gas. Have to admit it, hoods to aero hoods figures are scary. Not sure I can face riding on the hoods normally again :lol:

EDIT: worth noting that Cav doesn't use Cervelo's aerobars, he uses the ENVE's which are deeper.

Exar
Posts: 341
Joined: Wed Mar 01, 2006 10:28 pm
Location: The Netherlands
Contact:

by Exar

Quite a different result than what Tour Magazine came up with a year ago, especially for the Propel.
Chains to the right!

User avatar
rossjm11
Posts: 151
Joined: Tue Mar 03, 2015 8:09 pm

by rossjm11

Yeah I do not put much validity on this. If they don't run the same bar width and the same cockpit setup as control, then any small changes could easily be attributed to the cockpit. Either way though, to me this shows how relatively small the differences are between the bikes. So in my opinion, the one you felt best on would be the one that makes you the fastest.

Also, using 90mm wheels is fine, but why not also do the test with a pair of 60s... I find in my local racing that most people are on 60s, which could make one frame different than the others.
BMC SLR01 2015
Redline Conquest Team

BigCol
Posts: 23
Joined: Tue Apr 07, 2009 10:03 pm
Location: UK

by BigCol

For consistency, the bikes were set up in as close a riding position to each other as possible and the same wheels were used in all the bikes. The reason for this is that we wanted the variable to be the bike frame itself and not the rider or wheelset.
Read more at http://www.cyclingweekly.com/news/produ ... oC4ZODY.99


So not identical? How close were they? If the giant was an inch shorter and more upright for example surely this would be very significant? To be a meaningful test surely the position would need to be identical, not just as close as possible??

Col.

User avatar
kgt
Posts: 6717
Joined: Sun Jun 18, 2006 10:29 am
Location: Athens, Greece

by kgt

Guys, don't try to find a logical argument behind the results of these tests. There is not one... Just an inside game of companies and magazines that has nothing to do with science.

User avatar
BRM
Posts: 817
Joined: Sun Mar 16, 2014 3:43 pm

by BRM

Exactly these kind of so called tests are only to draw people to a site or magazine.
A marketing trap. Tests work as a magnet on people. It's a psychological thing.

Shrike
Posts: 1071
Joined: Fri Jun 03, 2016 5:08 pm

by Shrike

They're also fun and generate a bit of chat. Nothing wrong with it. And besides, I bet the data is valid and repeatable. These guys got the results they did for a reason. They won't tell the full story, and that's for us to fill in - which is the fun part.

If you have any of these bikes you're a lucky man. It's all good.

I'd have liked to see a more traditional frame used as a control, but no company would 'allow' that I bet.

User avatar
jekyll man
Posts: 1306
Joined: Wed Apr 25, 2007 10:23 am
Location: Pack filler

by jekyll man

Shrike wrote:, I bet the data is valid and repeatable.

.


:lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol:
C'mon this is cycling weakly you're talking about....
Official cafe stop tester

jeffy
Posts: 1242
Joined: Sun Oct 05, 2014 11:51 pm

by jeffy

what are the frame sizes, wouldn't be to difficult to use the same bars, and use different stem positions to get as close as possible to identical setup.

the jump up to the propel could easily be accounted for by rider position in the wind.

Imaking20
Posts: 1467
Joined: Fri Nov 18, 2011 5:19 am

by Imaking20

I think this actually tells a lot about efficiency of certain postures and cockpit configurations. Specialized put a lot of effort into those goofy bars, obviously with an emphasis on riding hoods (where people spend most of their time). And this demonstrates they were reasonably successful.
It looks like the complete cockpit integration of the Vias, Madone, and Aeroad are worth something (perhaps more than the frame?)
And the flappy cables hanging off the Propel aren't aero (shocker)
Current:
T2

Retired:
Blue | Project C6.0 | Felt AR FRD | Colnago C59 NERO | 2014 S-Works Tarmac | S-Works Venge | Wilier Cento Uno SL | Tarmac SL2

wingguy
Posts: 3527
Joined: Thu Mar 08, 2012 11:43 pm

by wingguy

Imaking20 wrote:Specialized put a lot of effort into those goofy bars, obviously with an emphasis on riding hoods (where people spend most of their time). And this demonstrates they were reasonably successful.

How do you figure that?

mr4fox
Posts: 252
Joined: Sat May 15, 2010 2:01 pm

by mr4fox

So do we have to add the watts for drive train and rolling resistance to these numbers to get the actual watts required for "45kph" in the velodrome? Even in a calm day 300w in an aero position with forearms on on the tops buys me closer to 40kph outside


Sent from my iPhone using Tapatalk

by Weenie


Post Reply
  • Similar Topics
    Replies
    Views
    Last post