The Gear Loop is supported by its readers. When you buy through links on our site, we may earn an affiliate commission. Learn more

(The Gear Loop) - Specialized’s Crux model was once reserved for hardcore Cyclocross racers - those brave folk who endlessly pedal around boggy circuits and resort to hulking bikes on shoulders when the going gets too tough. It’s hellish, but some people love the punishment.

However, the explosion in popularity of gravel riding, or simply the desire to mix up surfaces when out for a weekend spin, means there’s a new breed of buyer that is looking for the toughness of a gravel bike with the race-ready performance and components of a thoroughbred CX machine.

-

Matt Buckley/The Gear LoopSpecialized S-Works Crux review: action shots photo 2

The latest Crux, which Specialized says is the lightest gravel bike in the world, has arguably answered those prayers and now blends on-road manners with mud-plugging prowess and the ability to scramble up gravelly inclines likes a mountain goat better than the nameplate ever has before.

With a SRAM Red eTap AXS drivetrain, Roval Terra CLX wheels, a carbon S-Works SL saddle and ultra-lightweight seat post and finishing kit, the specification list reads like a bucket list dream build, which goes some way to justify the lofty £10,750/$12,000 price tag.

Matt Buckley/The Gear LoopSpecialized S-Works Crux review: detail images photo 4

But is that outlay all worth it? We spend a few weeks hitting the trails, pounding favoured road loops and getting knee-deep in boggy fields to find out.

Our quick take

Specialized seems to be hell bent on creating bikes that don’t fit into the usual sub-categories of late and seeing as there are more aerodynamic, race-ready cyclocross bikes available from rivals (check out the Cannondale SuperSix Evo CX, for example) and a more gravel/bike-packing friendly bike in Specialized’s Diverge, the latest Crux feels like it inhabits a little world of its own.

Matt Buckley/The Gear LoopSpecialized S-Works Crux review: detail images photo 1

There’s no mistaking this S-Works version makes for a phenomenal gravel machine, one that’s equally at home chipping away at the road miles as it is venturing off the beaten path, but then its devilishly expensive price tag means many riders might withhold from bashing it around the trails, which would be a shame.

It surprised us with is keenness to tackle tight turns, trample fairly bumpy descents and hop over gaps and tree roots. Throw on some wider tyres and it will likely handle even more, but its default set-up made it a machine we’d happily turn to throughout the year. Fast enough on the roads and agile enough for adventures, it’s arguably the perfect hybrid. It’s just a shame it costs as much as a hybrid... car.  

Specialized S-Works Crux review: the lightest gravel bike in the world brawls like a heavyweight

Specialized S-Works Crux

4.5 stars - The Gear Loop recommended
For
  • The lightest gravel bike out there
  • Phenomenal drivetrain
  • Nimble handling
  • A capable climber
Against
  • That price
  • Too nice to smash around trails?
  • Lack of mounting points

In the Loop

A quick look at the Specialized S-Works Crux:

  • S-Works Crux FACT 12r Carbon frame
  • Geometry inspired by road-going Aethos 
  • Tips the scales at just 7.25kg
  • SRAM RED eTAP AXS drivetrain and hydraulic disc brakes
  • Roval Terra CLX rims shod in Pathfinder Pro 2 tyres
  • Built-in crank power meter 
Matt Buckley/The Gear LoopSpecialized S-Works Crux review: detail images photo 17

A dream set up

You only have to scan the section above to realise that Specialized means business with this S-Works Crux. However, and as with most things in the Spesh family, there are much cheaper entries into the new Crux line-up, most notably the Comp variant, which costs £4,000 and comes with similar frame geometry, but a Fact 10r carbon set-up, a mechanical SRAM Rival groupset and less lavish finishing kit.

But wanting to show off this new bike’s prowess, Specialized handed over the range-topping S-Works model, which uses the marque’s highest grade of carbon fibre, which itself employed the same super computer wizardry as the recently released Aethos to banish any "lazy fibres" to the sin bin. In short, the computer creates a carbon lay-up that works the hardest, getting rid of any fibres that aren’t sweating it out to produce unrivalled strength in pursuit of lightness.

Matt Buckley/The Gear LoopSpecialized S-Works Crux review: action shots photo 5

The bike weighs just 7.25kg but it feels even lighter than that. So much so, that it’s actually a bit of a pain to rest against a bush/wall/car when you’re getting ready to ride or have stopped for a coffee. The faintest hint of a breeze has the eye-wateringly expensive set-up threatening to topple over. The answer? Never let go of it and never let it out of your sights. 

Throw a leg over, clip into your chosen pedals and the bike absolutely flies out of the blocks. Hit the slightest lump at speed and it actually takes off. It’s as if Specialized wanted this thing to become an extension of your legs. Spend some time with it and it almost disappears from underneath you.

Matt Buckley/The Gear LoopSpecialized S-Works Crux review: action shots photo 18

Predictably, the SRAM RED eTAP AXS electronic drivetrain is as crisp as you like, and the 12-speed/40T chainring combination rarely leaves the rider hunting for additional gears. The kerb weight has a big part to play in this, but it happily devours off-road climbs like the best road bikes smash Cat 1s.

This drivetrain also comes complete with a neatly built-in power meter, which is easily picked up by Garmin products and other bike computers.

Matt Buckley/The Gear LoopSpecialized S-Works Crux review: detail images photo 21

Specialized deliberately avoids mounting points for luggage, racks and mudguards, because this kind of negates the need for such a lightweight machine, but there are bottle cage mounting points in the usual spots, plus one underneath the down tube. If you really want to add weight, you can always look towards velcro-strap bike luggage.

Roval Terra CLX Disc wheels roll beautifully and perform admirably on-road, where they happily cruise at ballistic speeds. It feels weird smashing these thing along gravel trails, but they held up nicely on both rough rocks and loose gravel.

Matt Buckley/The Gear LoopSpecialized S-Works Crux review: action shots photo 9

This is helped, in part, by the 38mm Pathfinder Pro tires, which seem the right choice for those mixing up on-road and off-road riding. That said, there’s plenty of clearance to allow for up to 47mm tyres, should you be properly venturing into the wilderness. 

Tough on-road and off it

One of our favourite routes takes in pretty much every surface the S-Works Crux was designed to make mincemeat out of and it didn't take long in the saddle to realise that this thing is designed to tackle said route at twice the pace we normally would.

Matt Buckley/The Gear LoopSpecialized S-Works Crux review: action shots photo 19

It’s very difficult to ignore just how light the S-Works Crux feels, making the initial slog of bumpy blacktop miles an absolute breeze. Even with grippy 38mm Pathfinder tyres installed, it’s easy to cruise at similar to speeds as those keen beans on equally lithe road bikes. 

When it comes to new Crux, Specialized has taken lots of inspiration from its recently released Aethos, which on the surface looks like any fancy carbon road bike but incorporates bucketloads of tiny design elements and carbon fibre cleverness to create the ultimate in lightness and comfort: a carbon frame that actually soaks up bumps rather than shakes out teeth.

Matt Buckley/The Gear LoopSpecialized S-Works Crux review: detail images photo 9

It’s a similar story here and while attention has been averted from aerodynamics, plenty of time and effort has gone into lightness, robustness and overall ride comfort - all of which the new Crux majors on.

Point it in the direction of a steep climb (admittedly, there aren’t that many where we live) and it positively flies up them. The featherweight frame means new Crux feels responsive and eager to turn. It’s flatteringly simple to bunny hop it over cumbersome tree roots or flick the tail out during descents, for example. The grippy Supacaz Super Sticky Kush handlebar tape is also a nice touch, adding extra cushioning and the stickiest grip in hand. 

Matt Buckley/The Gear LoopSpecialized S-Works Crux review: action shots photo 2

Like the Turbo Creo SL Comp Carbon Evo we reviewed, the new Crux majors on the fun factor and despite its stupidly expensive and potentially frail-feeling frame, it urges the rider to start bashing it around technical sections, attempting a few minor drop-offs and generally getting it filthy. What's more, it is mega on the road too and shows very few weaknesses when out with ardent road riders. It makes a good case for a "do-it-all" bike, which might help justify the financial outlay. Or not. 

To recap

The price tag dangling from the lithe carbon frame of this top-end gravel bike will likely alienate many buyers, but look past it and you’re faced with an incredibly light, incredibly sharp climbing machine that feels just as happy eating up the road miles as it does tearing up dusty fire tracks and gravel paths. It’s a dream, bucket list bike, but you’ve either got to have deep pockets or a deep love for bashing gravel to commit.

Writing by Leon Poultney.