Specialized Roubaix SL8 Expert 2024

Specialized's Roubaix has earned its place as a go-to bike for those who value a smooth ride over an aggressive, speed-chasing riding position. The latest Roubaix SL8 model continues this legacy, but rather than a complete overhaul, it's been updated with some thoughtful tweaks. Specced with its newest third-generation Future Shock 3.0 front suspension system, mudguard compatibility and 40mm tyre clearance, the Specialized Roubaix SL8 Expert has proved an ideal companion for long rides and even for taking on some rough roads comfortably.

If you're interested in the Roubaix SL8, you might want to check out others in our guide to the best endurance road bikes.

> Buy now: Specialized Roubaix SL8 Expert for £5,250 from Tredz

While it may not be the lightest or the most aggressive endurance road bike on the market, the Roubaix SL8's smooth ride sets it apart. And though it comes with a hefty – if not quite as hefty as it was when I started my review – price tag, if smooth handling and comfort are what you're after, it's hard to beat, especially on the bumpy roads of the UK.

As a lover of long-distance rides, I've always liked the idea of the Roubaix and its promise of smooth-riding comfort. I first got to take it out for a quick spin at a press camp in Portugal, but although we did manage to find some slippery cobbles there, the roads were mostly buttery smooth. On home turf in Scotland, things are different, and I've certainly got to test its smoothing capabilities plenty in the last couple of months.

Specialized Roubaix SL8 Expert: Ride

From short after-work spins to all-day rides, including one 200km outing, the Roubaix has been as smooth as it promised. Even when the surfaces were sub-optimal, and even when fatigue started to kick in, the bike kept me free of aches and pains.

Despite the new Future Shock suspension – the main unique selling point of this bike – softening the front end considerably, it doesn't equate to a bike that handles weirdly. The 20mm headset suspension isn't the only thing contributing to the Roubaix SL8's smoother ride feel, either. With room for wider tyres – the S-Works Mondos fitted on my bike measured 34mm – the rubber effectively smooths out the initial bumps and gravel rattle, while the Future Shock absorbs the main vibrations before they get to the arms and neck.

I'll get on to the nitty gritty of the Future Shock in a minute, but as with any suspension, its function is connected to the rider's weight. This means that to get the best out of it, it needs to be customisable. I am very much at the lower end of the weight range (50-120kg) that Specialized lists for the different springs you can fit in, and I'd say that because of that I never felt the damping to be overly soft, even with the softest spring fitted in (you get three of them with the bike). Instead of feeling like a suspension fork-equipped bike, the Roubaix still feels like a road bike, but it just makes riding over road imperfections, speed bumps and the like a less bone-rattling experience. I could tell the shock was working, especially when climbing out of the saddle and weighing down the front more, but the system works up and down with you in a way that doesn't distract.

The Future Shock and wider tyres do add weight to the bike, though, and at 8.5kg with cages and pedals included this is not a lightweight climbing machine. That said, I could only really feel the weight on the steepest of climbs and when wanting to accelerate fast – it never felt like the extra grams were holding me back.

The rear end of the bike feels supportive but noticeably stiffer – possibly emphasised by the front-end suspension, and the fact that I'm a smaller rider. The Pavé seatpost and a lower insertion point add some flex, which you can see when pressing the saddle down and back, but it's a lot less than I've experienced with, for example, the Liv D Fuse seatpost. I don't see that as a negative: if you want efficiency then you can't make the whole bike overly damped, and the Roubaix feels very efficient munching the miles.

The bottom bracket area is also stiff and power transfer is great, even if the Roubaix is less reactive than a racier, rigid bike would be. With its slim fork and tube shapes, it's still aero enough to be pushed hard on the flats, and when the road tilts down I've found the slightly longer and relaxed geometry, paired with the suspension, keeps things very planted. The bike feels calm and composed rather than twitchy and overly reactive, which for an endurance bike is an advantage.

While sprinting isn't this bike's forte, it's helped me claim many personal records on descents because of its confident feel; the more at ease you feel on the bike, the faster you are going to go on it. That's certainly been the case with the Roubaix for me – it's helped me maintain speed a lot more efficiently than on my Specialized Tarmac, which in the small frame sizes gets a lot more nervous on high-speed descents.

If you're a weight-weenie or you prefer a super traditional ride feel, you might want to think twice, but if you're an endurance rider who values comfort without sacrificing too much speed, the Roubaix SL8 could be your new best friend.

Specialized Roubaix SL8 Expert: Frame details

So, the bike is nice to ride, but what about the tech details? The Roubaix has been in the American brand's lineup for a good while now, and with the newest iteration Specialized hasn't exactly gone wild and changed the essence of the bike – which was already well received as it was. The main differences on the newest model are the 40mm tyre clearance, some slight frame tweaks, and the updated suspension. The geometry is much the same, and despite the other changes, the promised – and delivered – ride quality is also akin to what you'd expected from the previous generation Roubaix.

The frame updates are pretty subtle and include lower seatstays, refined tube shapes for some marginal aero gains, and the generous seatpost flex. And when I say generous, Specialized is claiming a good 18mm of movement with this AfterShock system, which consists of the D-shaped Pavé seatpost with a dropped clamp design – the seat clamp sits 65mm deep inside the seat tube instead of a more traditional clamp that would sit at the top.

This leaves more seatpost free to flex but also means the Roubaix needs a longer-than-normal seatpost to allow the lower clamp to work effectively; it also accounts for the bulbous look of the seat clamp area. Whether you get exactly that 18mm of movement is hard to measure, but I could tell there was flex there.

Tyre clearance now extends to 40mm for light gravel use, which really does add to the bike's versatility, and the inclusion of mudguard mounts is a welcome addition for any of us in damper climes.

Specialized has also added two new mounting points: one on the top tube and the other on the underside of the down tube. You can add a bolt-on top tube bag without it interfering with the Future Shock, and the down tube mounts can take a third bottle or a tool caddy for longer rides – again, neat little additions with long distances in mind.

The result of all these changes, and a more advanced layup of the Fact 10r carbon blend, is a frame that Specialized says is 50g lighter than previously. It's by no means a bike for weight-weenies – weights start from 9.46kg for the base model, while the top-of-the-range S-Works Roubaix comes in at a claimed 7.3kg in size 56 – but my size 49 bike tipped the scales at 8.5kg including bottle cages and pedals, which is by no means heavy for an endurance road bike.

There are a few things that haven't changed: the frame still takes both electronic and mechanical groupsets, and the cable routing at the front remains external, which aesthetically might not please some, but I fully embrace the simplicity of service and setup changes that enables.

Specialized Roubaix SL8 Expert: Future Shock

Frame changes aside, the Roubaix's most notable feature continues to be the Future Shock up front, which is now in its third generation. The newest Roubaix bikes get one of the three versions of the system: the 3.1 with a simple coil spring and no damping (Roubaix Sport 105, Sport Apex and Base models); the 3.2 with hydraulic damping (Roubaix Expert and Comp), and the top-of-the-line 3.3 with adjustable compression. When set optimally, the suspension – which Specialized first introduced in 2016 – offers 20mm of travel, but there is now more adjustability through the spring rates and spacers than before.

The Future Shock system is placed between the head tube and the stem, so instead of this working to smooth out the bike, it's designed to suspend the rider. If the bike can move underneath you, Specialized claims, that should lead to less fatigue, especially on longer rides, and my experiences bear that out.

Though the proprietary nature of the Future Shock can be a buying deterrent for some, taking it apart doesn't require special tools, and after you've done it once you're not likely to think it was all that complicated (or you can take it to a shop for a service, as it is all serviceable). It also has added seals and the boot is thicker, which should extend service intervals.

Even if you leave the headset as it is, there is one thing that might require you to open the headset to get the most out of the bike: changing the booster spring, which comes in three different preloads. The three options – firm, medium and soft – are, according to Spesh, different in terms of their spring load from those used on the Future Shock 2.0. All of the Roubaix SL8 models come with the medium-strength (black) spring fitted in, but you get the other two with the bike in case you want to swap. You also get five preload washers which can be used to further tweak the spring tension. As I mentioned earlier, I rode with the softest spring and no spacers (which would add a little bit more stiffness).

If all that isn't enough adjustability, the 3.3 model with its five-step compression adjuster (and ability to switch off the damping) is the best at tailoring the damping, but you only get that on the S-Works and Pro models as stock. You can upgrade later if you want, and similarly, if you have an older generation Roubaix you can put one of the 3.0 Future Shocks in (only from size 49 upwards because of its longer length, though).

Specialized Roubaix SL8 Expert: Geometry

With these minor frame changes, it comes as no surprise that the new geometry of the Roubaix SL8 is not too significant a departure from the outgoing model in terms of reach and stack. But some numbers have changed, mostly to create clearance for those bigger tyres.

There's a slightly slacker head tube angle, more fork offset and an extended front centre which means the (now bigger) front tyre stays away from the toes. The chainstays are also longer, and the bottom bracket is pretty low at 80mm. All of this correlates with the very reassured ride feel.

For the rest of the numbers, my size 49 frame has a 992mm wheelbase, 549mm stack and 363mm reach. The seat tube angle sits at 74 degrees and the head tube angle at 70.8 degrees.

The smallest frame size, 44, does see a jump in the seat and head angles – both by a degree, to a steeper setup – but overall, for a small frame these numbers are good, and certainly slacker and more orientated to neutral or calm steering.

If you're someone who rides low and slammed, then the Roubaix probably isn't the best option. It does come with two headset covers to adjust the stack, but there is only so much tinkering you can do to the front height with the Future Shock installed. Specialized hasn't helped the stack height on stock builds by kitting the Roubaix with the hover bar, but you could still make some changes to lower the front end: opt for a simple flat-top road handlebar instead of the hover that adds 15mm of rise to your setup, and fit the lower headset cover.

If you fitted the lower headset cover and a normal non-riser bar, you'd already be 20mm lower, and I'd perhaps go for a slightly longer stem than the 80mm the size 49 frame comes with, too. I was fine on the bike as it came out of the box, but I'm thinking it wouldn't hurt to be slightly lower while my flexibility still allows it.

Apart from that taller front end, the Roubaix's geometry isn't miles away from bikes such as Liv's Avail (and Giant's Defy) and Trek's Domane, both also aimed at the endurance road market. Those bikes are a smidge longer but, at the same time, considerably lower. It's also akin to the newest Canyon Endurace's geometry. It really depends what you're after in deciding which is best for you, but generally, the Roubaix will give you a more upright position.

Specialized Roubaix SL8 Expert: Build

Specialized is offering the new Roubaix SL8 in seven complete builds and as a bare frameset, with prices for complete bikes ranging from £2,500 for the base Roubaix SL8 up to £12,000 for the S-Works model, which Dave already reckoned was "alarmingly expensive" when he reviewed the previous model, retailing for £9.5k, in 2020. 

While the flagship model features a SRAM Red AXS wireless groupset and Roval Terra CLX wheels, the Expert test model comes with a SRAM Rival AXS 12-speed groupset and Roval Terra C wheels.

There is a power meter, too, but it's a single-sided affair. If you want to know more about Rival AXS, we've done a full review, and I agree with what Mat says about it.

The wheels are wrapped in 32mm-wide S-Works Mondo 2BR tyres, which actually measured up at nearly 34mm. 

The alloy Hover bar is comfortable and grippy, but I'm not quite sure why it's supplied with this bike as it simply raises you even higher at the front. I like the shape, and the drops are comfy, but I would have preferred a standard non-riser bar. I doubt I'm alone in thinking this way. Also, only the Pro and S-Works models get a carbon bar.

The saddle and seatpost are also from Specialized, and the handlebar is wrapped in Supacaz Super Sticky Kush tape, which is on the thinner side but very grippy.

Specialized Roubaix SL8 Expert: Value

A year after its official launch, the Expert model is £5.5k, and can be found for less at many online retailers, but when I started to write this review the full RRP stood at £6k. If Specialized hadn't dropped some of its prices with the 2025 stock rolling in, I'd have said this wasn't the best value bike out there.

You can still get a better groupset on other bikes for the same money, but the new lower RRP isn't totally unjustifiable. The Roval Terra C wheels are pretty reliably built (if not the lightest) and even gravel ready, and the saddle and seatpost are great.

It is up against some serious competition, though. The Liv Avail and Giant Defy have both been updated recently and scored very highly in our reviews. The Liv Avail Advanced Pro 0 that Emma reviewed is £5,999, so slightly more than the Roubaix Expert, but it also gets a Shimano Ultegra Di2 groupset, a dual-sided power meter, carbon finishing kit and a lighter wheelset. The same goes for the Giant Defy.

The newest Canyon Endurace CF SLX continues to lack mudguard mounts and has less tyre clearance than the Roubaix, but it does have pretty neat top tube storage. You also get DT Swiss ERC 1400 Dicut wheels and SRAM Force AXS for less than the Roubaix (£5,149), or even less if you opt for Shimano Ultegra Di2 R8100 (£4,849), and you get a power meter.

We haven't reviewed a Trek Domane on road.cc since Mat put the SL Disc through its paces in 2021, but on paper the current Domane SL 7 Gen 4 promises much the same on the versatility and comfort front as the Roubaix SL8 Expert, but costs £6,100 – though you do get an Ultegra Di2 groupset. It's also the only one of these rivals with suspension, in the form of its rear-damping IsoSpeed.

Specialized Roubaix SL8 Expert: Conclusion

The Roubaix SL8 delivers the 'smoother is faster' ethos it's built upon. It's an excellent option, especially if you struggle with fatigue-related issues on longer rides, and it can double up as a light gravel bike.

With its lower retail pricing, it's not bad value, though ideally I'd like to see it equipped with a SRAM Force AXS groupset, and with the Future Shock 3.3; the suspension works well without the adjuster dial, but having the option to fine-tune the ride would have added value.

Overall, though, it's a bike that few other endurance all-road bikes can trump in terms of its sublime and smooth ride quality and the versatility that 40mm tyre clearance allows. For me, it's an ideal mile-munching companion and I'll be sad to part ways with it. If you can throw in another two grand and get the full carbon finishing kit and adjustable Future Shock 3.3, you'd likely never have to think about buying another bike again.

> Buy now: Specialized Roubaix SL8 Expert for £5,250 from Tredz

Verdict

Sublimely smooth bike that is capable, versatile and comfortable without compromising performance