Giant ToughRoad SLR GX 0 2018 review: Budget-minded adventurer

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Gravel is one murky sub-segment of cycling. Ask five riders to define gravel riding and you’ll likely get at least that many divergent answers, and one brand’s gravel bike might be noticeably different to another one. And yet, however hard it is to define, there’s no denying that cyclists are flocking to unsealed roads, long-lost paths and previously boring mountain bike trails as quickly as tensions with other tarmac users rise.

Group road rides, commuting, bikepacking or fire road shredding – a gravel bike can do it all (or so the industry claims). Depending on what you’re trying to do, it may not be the most efficient or the most comfortable, but it’ll get you through it and to where you’re wanting to go. Some gravel bikes balance the subtly different usages impressively well, while others, such as the Giant’s new ToughRoad, lean to a specific segment. And the ToughRoad does it at a budget price.

A typical gravel build

Story Highlights

  • Purpose:Versatile gravel or off-road bikepacking rig on a budget
  • Highlight:Burly build ready for big rubber
  • Frame Material: Aluminium
  • Brake type: Disc
  • Price: AU$2,399 / US$1,735
  • Weight: 9.95kg / 21.94lb (medium, w/o pedals)

Over the past few years, Giant have had their share of bikes that could be classified (or used) as a gravel bike, and yet, the new value-oriented aluminium ToughRoad SLR GX is one of the manufacturer’s first offerings that specifically mentions the “G word.” Bordering somewhat on the “monstercross” or even bikepacking end of the gravel segment, the ToughRoad GX is a difficult bike to catergorise, especially given that the ToughRoad SLR platform isn’t even devoted to the drop-bar gravel category. There’s another version, which drops the “GX” moniker, that features a flat handlebar and otherwise much of the same build.

For the drop-bar GX version, it’ll certainly do gravel. It can fit fat 700c rubber. And it is ready for pannier racks, too. In many ways, it’s a different beast to the performance-orientated gravel rigs we’ve seen pushed by comparably large bike companies, and is more akin to the smaller group of burly do-it-all gravel machines and off-road tourers from niche brands, such as those offered by Salsa or Otso.

No matter how murky the categorisation of a gravel bike is, there is some consistency in build kits between brands. You can typically expect disc brakes, knobby tyres between 35-42c in width, drop handlebars that are either flared or wider than normal, and a wide-range drivetrain, such as SRAM’s 1x-specific drivetrain that’s often visible on higher-end builds. The ToughRoad ticks all of these boxes.

Priced at AU$2,399 / US$1,735, the tested ToughRoad SLR GX 0 sits at the top of the ToughRoad range. Each ToughRoad SLR GX model features the same ALUXX SLR aluminium frameset (Giant’s top tier aluminium grade) and carbon composite fork with a straight aluminium steerer tube.

Giant ToughRoad SLR GX 0 2018 gravel frame
Every tube has been manipulated in some form.

The ToughRoad SLR frameset is what’s expected of modern aluminium from a leading manufacturer. Hydroforming was once a radical process, but Giant now regularly subjects nearly every aluminium frame tube to a mix of pressurized fluid and external moulds to form carbon-like frame shapes that were previously thought impossible in metal. The top tube on the ToughRoad SLR is slender and tapered from end to end, the seat tube has a D-shaped cross-section, and although the down tube was round when it was originally drawn, it’s now boxy and rectangular. All of the tubes are joined with consistent-looking TIG welds, and often by hand.

Showing the somewhat recreational utility intention of this frameset, there’s a kickstand mount at the rear dropout. Likewise, quick-release dropouts feature front and rear, a clear price consideration in a market where thru-axles are fast becoming the norm for anything with disc brakes. Giant may consider the standard threaded bottom bracket as another budget choice, too, but it’s frankly a welcomed feature to my eyes.

Giant ToughRoad SLR GX 0 2018 gravel bike SRAM Apex 1 drivetrain
Pannier mounts are kept hidden behind these plates until required.

The front and rear pannier mounts are kept rather subtle, hidden behind Giant-branded covers that provide a cleaner look if you’re not interested in using racks or fenders. It’s a similar story on the fork, with the nearly flush mounts sitting quietly until required.

Giant first introduced D-shaped seatposts on the Defy range of endurance road bikes, and it’s now a common theme through much of the range, including on the ToughRoad SLR. According to Giant, the flat back is more flexible than a round post, and with so much of it sticking out of the sloping frame, the aim is a more comfortable ride. The post is held with an integrated wedge-type binder that sits within a hollowed-out nook in the top tube.

There’s so much tyre clearance on the ToughRoad SLR that you’d be excused for thinking it started life as a mountain bike that had been converted for gravel use. The gaps surrounding the 39.5mm-wide tyres (measured width) are more obvious than Madonna’s front teeth.

Giant ToughRoad SLR GX 0 2018 gravel bike rear tyre clearance
Plenty of clearance surrounds the 700x40c rubber.

No doubt, the ToughRoad is ready to be expanded for truly cruel off-road mischief. An enormous 700x50mm tyre will fit in the 60mm-wide space between the chainstays – likely with room for a fender – and although it was tight, I even managed to squeeze a 29×2.25” (53mm actual width) tyre in the back.

The fork widens the gap further to 75mm, leaving space for a fender around that same 29×2.25in tyre. The 425mm axle-to-crown length is a substantial 43mm taller than Enve’s Gravel Road Disc fork, too, although that’s still not quite long enough to be swapped out for a mountain bike suspension fork without affecting the frame geometry.

Giant ToughRoad SLR GX 0 2018 gravel bike XFender downtube guard
The ToughRoad hides its cables beneath the X-Defender down tube guard, which also serves as the mount for the included mini-fender shown here.

Only the front brake hose is routed internally, entering the carbon fork at the crown and then popping back out down near the dropout. Otherwise, the full-length gear housing and rear brake hose run along the bottom of the down tube, shielded by a plastic bolt-on down tube protector. Three bolts secure the full-length guard to the frame, while an optional front fender can be bolted on over the top of the protector.

As tested, the ToughRoad SLR GX 0 offers a solid build kit that mimics high-end bikes from the performance end of the gravel segment. The 1×11 SRAM Apex 1 HRD drivetrain combines a 40T chainring with an 11-42T cassette, the same ratios used on the recently tested Cannondale SuperX SE, and further proves the off-road intention of this bike. That SRAM groupset also includes hydraulic Apex disc brakes with 160mm front and rear rotors.

Inline with every other 2018 Giant bike pitched at the enthusiast rider or higher, the ToughRoad comes set up tubeless. This means Giant’s own 40c CrossCut Gravel 2 knobby tyres and PX-2 wheels are shipped without tubes, but rather two small bottles of relabeled Stan’s tyre sealant.

The rest of the build kit also carries Giant’s branding, including the alloy flared drop bar and square-profiled stem. A Giant saddle sits atop the composite D-Fuse post.

All told, my complete sample weighed 9.95kg (21.94lb), without pedals but with the front fender. Light the ToughRoad SLR GX 0 is most certainly not, but that’s to be expected given the price point.

What is this thing?

As dumb as it sounds, it took some time before I figured out exactly what the ToughRoad SLR GX was trying to be. Its build kit shouts new-age gravel, but the general frame design and geometry figures are clearly eager to be loaded with bags and ridden until food rations run low. Having ridden the ToughRoad on road rides, rocky trails, and gravel grinds, I can attest to it loving the dirt, and being somewhat of a drag on the tarmac. On the road, the ride is akin to pedaling a decent 29er mountain bike: upright and with the persistent rumbling of tyre drag.

ToughRoad SLR GX frame geometry
All sizes of the ToughRoad share a 70mm bottom bracket drop, 42mm fork rake, and 450mm chainstay length. The wheelbase on a medium is 1048mm.

The weight obviously plays into the overall feel, but the frame geometry is also clearly better suited to off-road excursions. Stretched 450mm chainstays and a lazy 70.5-degree head tube make for a long wheelbase that great favour stability over agility. Yet the 42mm of fork rake yields a lot of trail, and a lot of “wheel flop.” It’s something you notice most in loose corners, with the front tyre feeling like it wants to wash out. Larger sizes offer a half-degree steeper head tube and are likely to be a little better off in this department, but not in a major way.

Such a high trail figure can be forgiven on a bike that’s carrying a heavy rear load, but even still, a little extra fork rake would be welcomed here. Not only would it liven up the handling, it may also be just enough to fix the slight toe overlap with the front wheel (which is pretty normal in smaller-sized gravel bikes). Changing the fork is a possible fix, but it’s something a buyer of a bike at this price shouldn’t need to consider.

Razor-sharp agility may not be the ToughRoad’s strong suit, but it does get better the faster you go – and the rougher the terrain gets, the more the ToughRoad and its tall front stance shines. I found myself motoring along a rocky firetrail at 40km/h, my skinny biceps flapping like I was riding Roubaix cobbles and the tyres kicking up all sorts of debris. Despite the chaos, the ToughRoad felt planted and eager for more, and was never unnerving.

Likewise, that “don’t give a damn” stability lends the ToughRoad to being a great commuter. Swap the tyres out for something smoother, load it up with lights, fenders, and panniers and it’ll serve you well.

Giant ToughRoad SLR GX 0 2018 gravel bike D-Fuse seatpost
Giant’s D-Fuse composite seatpost works as claimed. There is a visible amount of flex.

Aluminium frames have come a long way from the filling-rattling ride of years past. With its high-volume tubeless rubber, subtly tapered tube shapes, and visibly flexible D-Fuse seatpost, the ToughRoad’s ride is akin to sitting on a padded wooden stool. Your hands don’t get the same benefit, though, as the alloy steerer doing little to keep shock from coming through the handlebar.

Giant ToughRoad SLR GX 0 2018 gravel bike
The ToughRoad is capable of handling much more than the lightly loaded setup shown here.

Those long chainstays help to create a stable ride, but also provide clearance for panniers. The aluminium frame is certainly up to the task of being weighed down, but it’s lacking in accessory mounts with just two bidons and those front and rear panniers accounted for. Plenty of strap-on options exist, of course, but they’re obviously not as clean-looking.

The 40T chainring and 42T sprocket out back seem like plenty at first glance, and indeed, it provides a much easier gear than a compact crank with an 11-34T cassette. however, there were times I still wanted more. And certainly, if you’re looking to load this bike up like it’s intended and hit the hills, you likely will, too. Sizing down to a 38T chainring may be warranted, but you’ll be giving up top-end speed as a result.

Likewise, the narrow-wide chainring and clutched rear derailleur should provide ample chain security – at least in theory. But I found the limits of the design, throwing the chain on the same Roubaix-like jaunt I mentioned earlier. Granted, this was a very unusual occurrence and goes to show the type of terrain I was in where, other than the dropped chain, the ToughRoad was still laughing. Interestingly, Australian compliance laws require brands to provide geared bikes with a chain guide (some brands chuck a low-level front derailleur into the box to pass), and Giant did so with a reasonable quality resin chain guide. I initially chose to forgo it, but it’s clear that it’d be a good idea to keep it installed if you aim to test the ToughRoad’s limits.

Giant ToughRoad SLR GX 0 2018 gravel bike SRAM Apex
SRAM’s Apex 1 HRD levers share an identical shape to the Rival and Force 1 levers.

SRAM’s road groupsets are masters of trickle-down, incorporating not just the same features on lower-end versions as the premium ones, but actually sharing most of the individual parts across the board. As such, the SRAM Apex 1 levers have the same hood shape and ergonomics of Rival 1 and Force 1, with the same comfortable and secure grip when riding off-road.

Even so, the Apex hydraulic discs offered the smooth and easy lever feel expected of a hydraulic system, but the levers still lacked the snappy return and feedback of higher-end models. I also experienced some squeal under heavy braking, a noise I haven’t heard from more expensive SRAM brakes as of late. Whether this is due to flex from the quick-release wheel retention, a failure to fully bed in the brakes, or simply contamination from the factory, I, unfortunately, don’t have an answer.

The rolling stock is a surprisingly good-quality setup given that the entire bike costs less than most wheelsets we typically review. The 19mm (internal width) tubeless alloy rims will take a beating, while the butted spokes and sealed bearing hubs should provide a reliable service life with minimal maintenance. However, such dependability at this price comes with an obvious weight disadvantage, and the wheels, along with the tyres, take a fair amount of effort to get up to speed or when tackling slow gravel climbs.

Giant ToughRoad SLR GX 0 2018 gravelcut tubeless tyres
The Crosscut Gravel 2 tyres are well behaved on a mix of terrain, but a higher-end tyre will offer a noticeable improvement in other ways.

The tubeless tyres have proven durable, and while they’re well-rounded off-road, my preference would be to swap them for something a tad wider, a little more supple, and faster. This would further smooth the ride, save some grams, and ease your pedaling time on the road and smooth gravel.

The rest of Giant’s components do the job well. The flared bars provide greater control and stability off-road, but the reach is also a little long for my liking. And admittedly, I’m not a fan of the somewhat narrow saddles typically found on Giant bikes, but given how personal such things are, it’s hardly a criticism.

Finally, I think Giant’s entire “adventure” range, consisting of the Revolt (discontinued), the AnyRoad, and now the ToughRoad, all share a similarly unusual and polarising aesthetic. To be fair, the ToughRoad is certainly the nicest of the bunch, and the subdued charcoal paint and boxy shapes give it a rugged look, but the highly sloping top tube and compact frame is sure to scare many traditionalists away.

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