Given recent threads on the 2015 Cervelo S5, the Felt AR and the new Canyon Aeroad CF SLX, I'm amazed nobody has picked up on the latest aero road bike tests by Tour Magazine. While the full analysis is available in the latest Tour International issue, the raw drag plots using the Tour half-mannequin are openly accessible online. I'm aware that people have pointed out caveats to the Tour testing protocol but it's still the best – indeed only – independent comparative data we have on these new models. IMO even if there are failings they should be applauded for their work.

A few Clif notes:
- With the same Zipp 404 wheel set up it is pretty much a wash between the S5, the AR FRD and the Canyon Aeroad (each with their own, sometimes proprietary aero bar)
- Lower range models from each manufacturer were also tested, with wheelsets they came with and then with Swiss Side Hadrons. Looking through the results for models with identical frame forms (e.g. the Felts) suggests that the Hadrons are effectively as aero the Zipp 404s.
- Negligible difference between the AR FRD with 404s and aero handlebar vs AR3 with Hadrons and standard handlebar; does the aero handlebar have little benefit, or a failing in the Tour testing protocol?
- Cervelo S5 with HED Jet 6 Plus SCT faster across almost all yaws (including zero) than with the 404s. Would the HEDs have the same effect on the Felt and Canyon? Are the HEDs currently the fastest wheels at 60 mm depth?