..........................................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
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."
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.
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
EDIT: worth noting that Cav doesn't use Cervelo's aerobars, he uses the ENVE's which are deeper.
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.
Redline Conquest Team
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??
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.
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)
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