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(The Gear Loop) - It’s easy to get caught up in the Aethos marketing bumf, with Specialized claiming they "stopped worrying about winning" when designing their new machine and instead chased "the greatest expression of ride quality ever made". They also apparently "broke all the rules" of carbon fibre manufacturing.

This sort of stuff makes us roll our eyes a bit, because £12,500 seems like a lot of money to part with for something that isn’t a razor sharp, wind-tunnel-tested aero machine that can basically transform very average riders like ourselves into Tour de France stage winners.


Angus Sung/SpecializedSpecialized S-Works Aethos review photo 2

But it doesn’t take many miles in the saddle of the range-topping S-Works Aethos to realise this is a very special bike - one that blends all of the performance qualities of the marque’s own championship-winning Tarmac SL7 with a much more laid-back everyday demeanour. 

Plus, let’s not gloss over the fact that Specialized offers builds of this bike that weigh just 5.9kg. That’s so light, the UCI won’t even let it compete in any of its sanctioned races. So does it make it pointless? Not really, because this is arguably the ultimate expression of a weekend warrior, a hideously expensive and over-performing sportive machine that will no doubt bring deep joy to its owner, so long as they have deep pockets.

Angus Sung/SpecializedSpecialized S-Works Aethos review photo 5
Our quick take

When we talk about bikes that adopt the upper echelons of the price stratosphere, it opens up a can of argument-inducing worms. For a start, you can go to someone like Argonaut and have a custom carbon bicycle built to your exact specification for similar money. 

It also opens up the world of hand-made and hand-painted Italian frames from the likes of Colnago and aerodynamic, world-beating wonders like the Pinarello Dogma F. But maybe that’s not what you want. Maybe you like to keep things on the down-low. 

Angus Sung/SpecializedSpecialized S-Works Aethos review photo 6

If that’s the case, the Specialized Aethos is excellent, offers a truly remarkable ride and it doesn’t like to shout about it. Plus, it feels like it can pound the blacktop day in, day out without any complaint from the bike or rider. 

That said, there are cheaper versions of the same model available, but none sport the same fantastic FACT 12r carbon frame, which we feel is the frame Specialized is most proud of and really wants you to ride. In short, you’ll just have to start saving if you want the full Aethos experience. 

Specialized S-Works Aethos review: a performance road bike for the (rich) people

Specialized S-Works Aethos

4.5 stars - The Gear Loop recommended
  • Climbs like a champion
  • Impossibly light
  • Stylish
  • Effortless to ride
  • The price
  • Looks better in rowdier colours
  • Limited wheel options
  • Lacks aero touches some might demand


In the Loop

The Specialized S-Works Aethos in a nutshell:

  • At 585g, the Aethos is the lightest production disc frame ever made
  • All models come with powerful disc brakes
  • Entry level Expert model comes with Shimano Ultegra groupset
  • Range tops out at £12,500 Shimano Dura-Ace Di2 model
  • Built-in dual-sided power meter
  • S-Works SL alloy stem and bars
  • Roval Alpinist CLX carbon rims shod in 26mm Turbo Cotton tyres 
  • Full carbon fibre Body Geometry S-Works Power saddle and Roval Alpinist carbon seat post
Angus Sung/SpecializedSpecialized S-Works Aethos review photo 8

Choice components

The S-Works Dura-Ace Di2 model tested here is arguably the creme de la creme of bike builds and as such, hangs pretty much every desirable component on that lithe, lightweight frame. That said, it’s nothing new, but that doesn’t stop it from being a joy to use.

The Shimano groupset shifts slickly and proves almost silent when riding hard, while the Dura-Ace R9270 hydraulic disc brakes are powerful and reliable in all conditions. Never once did they feel like they would fade on a descent.

Angus Sung/SpecializedSpecialized S-Works Aethos review photo 11

Roval provides both the wheels and the carbon seat post and both are excellent. Although there have been some murmurings from the diehard cycling community that the sole offering of one set of clincher wheels doesn’t exactly cover all bases.

Some folk will want to go tubeless and demand the ability to throw into the mix some wider tyres, which is perfectly possible given the room between the stays. If that’s the case, you’ll want to be swapping those rims out, which is another financial outlay, unless you’ve got them laying around the garage (lucky you). 

Angus Sung/SpecializedSpecialized S-Works Aethos review photo 12

It’s also fairly remarkable that the cockpit isn’t some one-piece carbon fibre masterpiece at this price and much of the cabling is visible. It’s just unheard of at bikes in this bracket, but Specialized wants it to be used everyday and therefore has made it easy to maintain and comfortable for most users. Hey, the press shots even hint that it's up for a little bike-packing.

Carbon cockpits are nice, but they’re not exactly your best friend when embarking on multi-day tours in the mountains. And have you ever tried servicing anything with internal cabling? Nightmare

The (pricey) people’s champion

It’s hard not to have the Aethos’ asking price rattling around your brain when first taking it out for a spin. A cool £12,500 is more than most people will spend on a family car. It feels crazy to be pedalling such a thing around our favoured but very average local route.

Angus Sung/SpecializedSpecialized S-Works Aethos review photo 10

But here’s the thing, nobody really knows. It’s not covered in go-faster stickers, nor is it some overly aggressive machine that looks like it’s just rolled out of McLaren’s wind tunnel facility. Those in the know, know, but otherwise it gets on with its business without too much fuss.

That’s the beauty of it, because it approaches road cycling with such a laid back attitude, yet performs like a machine that has been locked in a gym and told it will only be let out when it can chase and smash records.

Angus Sung/SpecializedSpecialized S-Works Aethos review photo 14

The frame is both stiff but surprisingly comfortable, with fantastic power transfer, while the featherlight overall mass means it positively glides along the flats with minimal effort. Point it towards a climb and it’s as if you’ve somehow integrated electronic assistance into your legs. Not only did we arrive at some of our favoured inclines feeling fresher, we also reached the summit with far less overall effort. Cornering? Yep, that's as sharp, as reponsive and as confidence-inspiring as you'd ever hope for. 

This test model was supplied in a small, as this rider annoyingly bridges the gap between a small and medium frame, and it did feel a little on the teeny side. But that didn’t hinder any enjoyment (or make it uncomfortable)… it almost added to the sense that we were essentially riding a cloud with wheels.

Angus Sung/SpecializedSpecialized S-Works Aethos review photo 13

Specialized claim they introduced some kind of fancy computer algorithmic wizardry when settling on the optimal carbon fibre lay-up of the Aethos, something it has revisited with the equally fantastic Crux gravel bike, so this means every single fibre is made to work as hard as it can.

The unconventional shape of the frame - and tubes that make it up - are down to engineers (and software) deciding on the best location for additional layers of carbon to improve rigidity and strength. According to its maker, it used "longer, unbroken plies" of carbon, meaning every ounce is squeezed from every fibre, reducing weight substantially.

Angus Sung/SpecializedSpecialized S-Works Aethos review photo 18

Believe the science stuff or not, there’s no denying the bike rides beautifully and it manages to be razor sharp and confidence-inspiring through corners, while somehow promoting all-day comfort in the saddle. It climbs like a beast, too, and this means you spend more time enjoying the ride and less time focussing on your average performance. 


To recap

Rather than chasing podium wins, Specialized has focussed its efforts on creating a lightweight, high-performance road bike that seemingly excels in all areas. Where carbon-framed aero machines are often uncomfortable, the Aethos is a joy to ride for miles, and where more robust steel and aluminium bikes let the side down with overall mass, the S-Works Aethos tips the scales at just 6.23kg, but feels every bit as tough as an everyday steed should be. But like many things Specialized is pumping out these days, it’s hideously expensive.

Writing by Leon Poultney.