BMC worked hard to make the claimed 940g frame slippery at varying yaw angles, as well as head on. Along with aero profiles on everything, a key feature is the Aero Module, which sits between the down tube and seat tube and comprises both bottle cages and on-bike storage.
The Aero Module adds some storage
At the same time, the Di2 control box is integrated into the down tube, and the slick Integrated Cockpit System hides every hose and cable from the wind. There are even futuristic looking fairings that straddle the disc rotors, smoothing airflow around the calipers. The top spec Timemachine sports a Dura-Ace Di2 groupset and 62mm deep DT Swiss carbon clinchers. You have a choice of eTap hydraulic and Ultegra Di2 groupsets too.
The Specialized S-Works Venge is more practical than its predecessor, and faster
You know what they say, Venge is a dish best served aero. The old Venge ViAS helped set the trend for fearsomely complicated aero bikes with everything integrated and proprietary. It was brutally quick, and brutally impractical. The new S-Works Venge is a little more real-world, and it’s faster and lighter than ever. Specialized won’t say how much faster, but the brand does claim to have shaved 240g off the frame and added around 40–50 percent more compliance compared to the ViAs, although the Tarmac is still more comfortable.
Specialized developed the frame from a library of tube shapes it had built up from extensive aero modelling, and an understanding of what’s possible using current materials.Where previous models had gloriously inconvenient one-piece cockpit assemblies, the new Venge sports Specialized’s Aerofly II bar, a standard item that can be swapped out as you please.
The Venge uses a standard aero bar rather than an integrated design
The top of the range bike weighs just 7.1kg in a 56, and it’s designed for electronic shifting and hydraulic discs only.The standard spec includes Shimano Dura-Ace Di2 components, Roval CLX 64 carbon wheels and Specialized’s own power meter cranks, which feature left and right side measurement.
The Cannondale SystemSix has every aero feature under the sun
Claimed to be the fastest UCI-legal bike at the time of its launch, the SystemSix is Cannondale’s take on the integrated-everything aero bike.It’s a veritable cornucopia of aerofoil cross-sections, with all the hallmarks of a modern aero machine, and the messy bits hidden on the inside.
An important part of the package are the KNOT components, which include the cockpit, seatpost and wheels.The 64mm-deep KNOT wheelset uses rims that are a gargantuan 32mm at their widest point, and which have a healthy internal width of 21mm. Fat rims allow for later separation of the airflow, and hence lower drag.
Cannondale ships the SystemSix with tyres that are nominally 23mm wide, but on these rims they swell to something like 26mm. The rim-tyre combination claims the benefits of wider tyres without the aero penalty
Want to use that power meter? You’ll have to raid your bank account again
Like many such bikes, the top-end SystemSix includes a power meter as standard, but you have to pay an additional fee on top of the sale price to activate it. Pretty cheeky, Cannondale.
Gone are the split-legged forks and while there’s still a rim brake option, it’s the disc machine that impresses with its ultra-clean, fully integrated design. The wacky mini-V brakes of earlier generations are but a distant memory.Ridley cheats the wind by moulding channels into the leading edges of its tube sections, something it calls F-Surface treatment.These act as aerodynamic trip wires, which create vortices and delay separation of the airflow over the frame, reducing drag.
Ridley’s F-Surface aero trip wires are very cool
Even the headset spacers are channelled, and they blend into a gorgeous one-piece carbon cockpit with a super-low profile, which completely hides cables and hoses. Fast? We imagine so.
Trek Madone SLR 9 Disc
Trek’s Madone SLR Disc wants you to go fast, comfortably
Rider comfort used to be the Achilles’ heel of aero bikes, but the latest generation of designs sets out to address that. None do it more radically than Trek with the latest Madone SLR.The Madone uses an updated version of the brand’s bump-smoothing IsoSpeed tech, which partially isolates the rider from the road.
The seatmast assembly extends under the top tube, and pivots about the centre of the seat cluster. The amount of flex can be adjusted with a simple slider and rebound is damped by a small elastomer in the seat tube. The disc brake Madone is slightly heavier than its rim brake counterpart, but surprisingly it’s also more aero.
Whichever version you choose, the Madone comes equipped with a new two-piece aero cockpit which offers the clean integration of other slippery designs, but with more adjustability.
The ICON paintjobs are something else
Added to that, the bike is available in some truly eye-popping colour schemes, including six special designs that form what Trek calls Project One ICON.
If there’s one takeaway from all of this, it’s that aero bikes seem to have matured, and they’ve also started to look more and more similar to one another.
The concept of an aero road bike has been around for years, but this latest generation takes a more considered approach. More thought is given to comfort and practicality, while speed remains the driving force.
So, which aero weapon would you sell a kidney for?
You’ll be shocked to hear that 2019’s hottest aero bikes all have discs
Matthew Loveridge (formerly Allen) is an experienced mechanic and an expert on bike tech who appreciates practical, beautifully-engineered things. Originally a roadie, he likes bikes and kit of every stripe, and he's tested a huge variety of both over the years for BikeRadar, Cycling Plus and others. For a long time Matthew's heart belonged to the Scott Addict, but he's currently enjoying Specialized's sublime Roubaix Expert and having a torrid affair with a Giant Trance e-MTB. At 174cm tall and 53kg, he looks like he should be better at cycling than he actually is, and he's ok with that.