Aero test. Trek Madone, Venge, Cervleo S5, Giant Propel & Canyon Aeroad
Posted: Tue Apr 25, 2017 9:50 am
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."
..........................................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."