In our Tech Q&A series, we tackle cycling queries – big or small, complex or simple – with insights from the BikeRadar team and trusted industry experts. Next up, a reader suggests a new aero endurance genre for road bikes – but does such a genre already exist?
Can you encourage the bike brands to make an aero endurance bike that doesn't weigh a ton?
A good example would be a Specialized Tarmac SL8 or Cervélo S5 with a high stack height and short reach – essentially an endurance race bike that isn’t ugly.
P.S. I hate loud freehubs as well
Lifesurfer001 via email
Funnily enough, we think such bikes already exist!
Senior technical writer Simon von Bromley explains how Cervélo used to make an S5 with a higher stack.
The brand had a philosophy that it was more aero to run a bike with a higher front end than have a stack of headset spacers instead. But the pros didn’t like it, and they’d typically run negative-angled stems to achieve their desired positions instead. On later S5’s, Cervélo then switched to running its riser Carbon V Stem instead.
If you want something more conventional-looking, Cervélo’s Áspero-5 that Marianne Vos ran at the recent UCI Gravel Worlds Championship might be what you’re looking for.
It has clearance for voluminous 45mm tyres, does away with the V Stem and ships with 42mm-wide Vittoria Corsa Pro Control tyres that are currently only available on this particular bike.
Simon thinks the Áspero-5 might be a better bet than the S5 because it doesn’t rely on a proprietary front end so you can more readily experiment with the position – and it also doubles as a gravel bike to boot.
Beyond that, Simon suggests you can look at bikes like the Giant Defy, Cannondale Synapse or the Canyon Endurace, all of which we’ve rated highly.
However, bear in mind that if you’re chasing aero gains, it will often be at the expense of weight but weight isn’t the most important factor in the grand scheme of things. Plus, most aero-derived bikes are light in their top model guises.
We recently carried out an experiment with stack height, where we tested three different positions using an adjustable stem on a Specialized Tarmac SL8 to see whether higher is indeed faster.
Dutch cyclist and frame designer Arne Peters has been at the forefront of this trend, and he’s developed the Morpheus Reppit race bike with a super-tall head tube.
Peters' theory is that the taller stack height allows riders to adopt and, crucially, hold a more aerodynamic position with their forearms at 90 degrees, making it easier to tuck your head in, and in turn reduce frontal area.
It will be interesting to see whether mainstream brands adopt this way of thinking and only time will tell if a future Specialized Tarmac or Cervélo S5 switches to a higher front-end.
