Specialized S-works Aethos
Simplicity reigns
Every day’s a school day. I recently learned from an article by fellow journalist Carlton Reid that British marque Carlton Cycles made a carbon-tubed, alloy lugged bike back in 1971. Motor Cycle and Cycle Trader magazine reported at the time, ‘The weight of the complete machine is 13lbs 12oz,’ continuing that ‘most certainly the experimental Carlton in carbon fibre is the most exciting adaptation of modern materials to cycle building that we have seen for many years’.
Sadly the bike never went anywhere, but it struck me as wonderfully coincidental that I’m testing what’s claimed to be the world’s lightest production disc brake bike – the S-works Aethos – and its weight? It’s 6.23kg, or 13lbs 12oz in old money. Is anything new under the cycling sun?
Number, number, weight, division
The foundation of the Aethos is its 585g frame and 270g fork (claimed, 56cm), 1,248g Roval Alpinist wheels and 136g Roval Alpinist seatpost. Yet that’s about where the ‘special’ components end – everything else is pretty standard.
Of course Dura-ace Di2 and £240 S-works saddles aren’t exactly run-of-the-mill, but time and again brands dress up average-weight frames in ridiculous components – notably entirely unsuitable tubular wheels – so they can label their bikes ‘lightest ever’. The Aethos bucks that. It’s light but it has day-to-day usability. The wheels are clinchers; the bars and stem are twopiece, and the cables are – gasp – visible. So while you may want to change a tyre or cut the steerer, you won’t need an NVQ in needlework and brake bleeding. The saddle even has padding.
The only non-ordinary thing here is that the Aethos isn’t – further gasp – UCI approved, because it’s well under its 6.8kg minimum weight. So (a) Specialized has saved itself €5,000 on getting the certificate (I’m told that’s what it costs) and (b) in theory this is not for pro racers, with the Big S proclaiming, ‘Sod the rules, we want to make a bike for you.’
And, my days, if it hasn’t gone and made the best mainstream bike out there.
Too talented by half
Think of everything you want a road bike to be and the Aethos is it. The handling is superb. Specialized has borrowed the geometry of its brilliant Tarmac SL7, but when combined with the lightness of the Aethos the result is a bike that’s just that bit more responsive than the
SL7. Specialized has then blended this character with stability and a stiff punch.
Eddy Merckx said a lightweight bike cost Luis Ocaña the 1971 Tour when the Spaniard came unstuck on a bend, and you don’t argue with Eddy. But what Eddy can’t argue with is how well the Aethos descends, displaying none of the skittishness that plagues ultralight bikes, instead presenting the assured platform of a bike 2kg heavier. The frame flexes enough to track undulations and offer grip, but never so much it feels wavy. However, as brightly as the Aethos shines in those departments, it is outright retina-eviscerating in one specific area: climbing.
All bikes can go uphill if you pedal them hard enough, but what the Aethos does is ride up first, hook a motor winch to the crest then abseil down to collect you. This bike climbs like an invisible force is pulling it. It’s just brilliant, and this extends to acceleration too, where stiffness and lightness combine to make rocket fuel.
This bike climbs like an invisible force is pulling it. It’s just brilliant, and this extends to acceleration too
So are there any weaknesses? Well, it’s not an aero bike. To hit weight and stiffness targets Specialized has used round tubes. And again to save weight the paintjob is understated.
As a friend remarked, ‘Eleven grand for a bike that looks like it was made in 2012?’ And there’s a shred of truth to that, because although it blows every other mainstream bike out of the water, its pricetag moves it into a realm in which resides the Argonaut Road Bike (issue 84) and Prova Speciale (issue 91). Both are custom, so different beasts in a sense, but they’re stunning to look at and amazing to ride. The Argonaut remains the best bike I’ve ever ridden.
Then – and this is not a criticism, just a point of interest – the idea this is not for pros is murky. I bet the Aethos will end up being raced with ballast, and it may even suggest Specialized knows the UCI is poised to lower weight limits.
I do have one conjecture though: the wheels. These Alpinists are lovely to ride but they’re not tubeless, so I swapped in a pair of DT Swiss ARC 1100 50mm tubeless wheels with 28mm Schwalbe Pro One tyres. That added 17mm to the rim depth and 2mm more rubber yet little more than 300g in weight, and on balance I preferred this setup. Tubeless wheels are faster, more comfortable and I hate punctures.
Still, however you look at it, while crazy-light carbon bikes may have existed since the 1970s, never has one ridden this well. The Aethos is an absolute triumph.