What’s the difference between a cyclocross bike and a gravel bike?
Gravel bikes and CX bikes have their similarities – but they're not the same thing. Here's why.
Gravel bikes and CX bikes have their similarities – but they're not the same thing. Here's why.
Over the past few years, the gravel category has become one of the brightest lights in the cycling industry, with brands and consumers alike discovering the potential of wider tyres and an exploratory spirit. Gravel cycling can take you away from the beaten path, limit your interactions with distracted drivers, allow you to tackle a wide range of different terrain, and float back and forth between on road and off.
That cross-compatibility is a compelling sales proposition for riders searching for a new bike to add to the fleet. But the appeal of the gravel bike doesn’t lie just in it being a bike to add – its capability across surfaces means that plenty of riders are drawn to one as a single bike for all purposes.
You don’t have to think very far back to remember that there was once another style of bike that was seen in the same way.
Before the gravel category took off, cyclocross bikes filled a similar niche, and when ‘gravel’ began to emerge as a distinct category, many thought that gravel bikes were the same thing under a different name, cunningly devised by the industry as a means to sell more bikes.
But while there are certainly similarities between gravel and cyclocross bikes, it’s reductive to say that they’re the same thing. Let’s take a closer look at the two – where they match up and where they diverge.
At the 2021 CyclingTips Field Test, up in Victoria’s High Country in the beautiful town of Bright, a little bike company called Giant was kind enough to sling us a couple of bikes to ponder the defining question of our age: “what’s the difference between a cyclocross bike and a gravel bike?”
The two challengers were lean, mean and keen for a couple of bike journalists to pedal around on them. In the gravel corner, we had the Giant Revolt Advanced 0, and repping the cyclocross category was the Giant TCX Advanced Pro 1 (which we have much more to say about in the linked review).
These two bikes act as a handy proxy for the broader categories they represent – and at a surface level, there are some pretty obvious similarities to them.
For starters: they both have carbon fibre framesets of the same grade, and tubeless carbon wheels. They weigh a similar amount. They cost about the same amount – AU$5,499 for the TCX, AU$4,999 for the Revolt. They both have Shimano’s excellent GRX 810 groupset – although one is built up with a single chainring and the other has a front derailleur and 100% more chainrings. We even went to the trouble of setting them both up with the same tyres – Continental’s Terra Speed, in a 700 x 40 mm size – to try to eliminate as many variables as we could.
But that’s about where the similarities end.
To understand why, we need to take a couple of steps back from the nitty gritty of these two particular bikes, and take a look at the broader categories of cycling that they were designed for.
Let’s first take a walk down memory lane.
In the early 1900s, a weird, wonderful and wintery cycling discipline called ‘Cyclocross’ emerged in western Europe, with road racers of the age using it to hone their skills and scratch the competitive itch in the off-season. Based around a format that incorporates rougher terrain, muddy and snowy conditions, obstacles like barriers and steps and sections that require the rider to dismount and carry their bikes, cyclocross has since proven itself a popular spectator sport, attracting an enthusiastic following even beyond its European heartland.
A big part of that growth into a global phenomenon can be traced back to the 1940s. At that point, cycling’s governing body – the UCI – got involved. By 1950, this somewhat eccentric discipline had its first World Championships, and the sport of cyclocross took a major step toward international recognition.
The UCI stepping in meant a couple of major things. For one: there was a snazzy rainbow jersey for the winners each year. For two: things got official, with technical requirements and rules and countless numbered regulations.
The UCI’s sanctioning of cyclocross arguably had its most significant impact on the technical side of the sport, and in turn, on the development of the bikes that are used in the races.
The sport exists in a rigidly defined technological framework – most prominently applying to the tyre sizes permitted in competition, which are capped at 700c x 33 mm to ensure a more level playing field. Bikes are built to be fast, agile and responsive for the duration of a CX race, which maxes out at about an hour.
That means that cyclocross bike designers have an existing blueprint that they are required to work from, and – apart from major generational changes, like disc brakes and STI levers and the arrival of carbon fibre – it is a somewhat more stagnant category for innovation.
Gravel, meanwhile, is – for now – not sanctioned by the UCI, and as such is not beholden to any technological requirements. That means bike manufacturers have far greater latitude, and that the gravel category is more fertile ground. Bikes are designed not for a single hour of blood-in-the-mouth exertion, but for adventure. Bike designers can borrow features from cyclocross bikes, from mountain bikes, and from road bikes in varying ratios to create a new style of bike that melds aspects of all three.
As a result, the gravel category is far more diverse – and because it’s an area of growth, it’s also where a lot of the most exciting innovations in the drop-bar space are taking place.
Cyclocross bikes are most commonly – but not exclusively – available with aluminium or carbon fibre frames. They have a purposeful minimalism to their design that usually won’t include extraneous mounts for bottle cages or fenders or anything that doesn’t fit within the technological necessities of the sporting discipline.
In the past cyclocross bikes were slowed by cantilever brakes or mini v-brakes, which offer greater mud and tyre clearance than road caliper brakes. However, since disc brakes were first greenlit for CX competition by the UCI in 2010, these have become the dominant braking format and today you’d be hard-pressed to find a bike in the category sold without them. Which, as many cyclocross riders of generations past will probably attest, is no bad thing.
The gearing on cyclocross bikes typically features a reasonably narrow gear range with either a double chainring (typically with a 46/36 tooth configuration) or a single chainring. This is a reflection of the fact that you’re trying to get around as quickly as possible, want tight spacing between gears, and are unlikely to encounter any massive mountains on a CX course.
On the Giant TCX Advanced Pro, for example, there was a single 40T chainring and an 11-34T cassette, giving a suitable range for a CX race but quickly running out of range on mountainous ascents.
Because they’re built for racing, cyclocross bikes tend to offer greater stiffness through the frame and contact points for maximum power transfer, and as confident and direct handling as possible.
Gravel bikes are most commonly available in aluminium or carbon fibre frames as well, although you’re more likely to also encounter steel and titanium in this category. Where cyclocross exists in a clearly demarcated series of guidelines, ‘gravel’ is much more loosely defined, and as a result, there’s far greater diversity within the category. There are road-like gravel bikes that are built to go fast in races, dual suspension gravel bikes that blur the lines with mountain bikes, meditative adventure bikes with oodles of mounting points that nod towards touring or randonneuring, dropper-posts, and everything in between.
Although there’s a lot of differences within the category, one defining feature across the board compared to CX bikes is that gravel bikes are likely to offer far more generous tyre clearance. The vast majority of gravel bikes nowadays will be able to accommodate at least a 700×38 mm tyre, and in many cases, there’s scope for anything all the way up to a full-blown mountain bike tyre.
Increasingly, you’ll see gravel bikes designed around both a 700c and a 650b wheelsize. The 650b size – also known as 27.5” – has a smaller wheel diameter that allows higher volume tyres to be fitted while still maintaining the bike’s desired handling, meaning that you’ll be able to fit a wider tyre for a similar diameter and eke out a little extra plushness and tyre contact patch.
To reflect the more diverse terrain that gravel bikes are likely to tackle, they will typically come with a wider gear range. These can be either 1x or 2x.
1x groupsets give increased simplicity, slightly lighter weight due to the lack of front derailleur and a cog, fewer duplicate gears, and more chain security, thanks to the use of narrow-wide chainrings and clutched rear derailleurs. 2x groupsets can offer a wider gear spread with smaller jumps between, making it easier to find exactly the right gear for a desired pedalling cadence.
The Giant Revolt Advanced 0 that we tested incorporated Shimano’s excellent GRX 810 groupset, with a double chainring (48/31T) and an 11-34T cassette. That gave a generous gear range that accommodated anything from spirited road riding to much more adventurous riding, with tighter spacing than an equivalent range on a 1x setup.
Gravel frames tend to be tuned with a little more comfort in mind over longer rides, transferring fewer vibrations from the surface to the rider compared to the race-oriented cyclocross bike.
All of these factors mean that gravel bikes can be far more capable than a cyclocross bike, which exists within a more rigidly focused definition of what the bike must be.
If you’re looking for specific buying tips and advice, check out our guide on how to choose a gravel bike.
Cyclocross races are a brief, all-out effort that push you into varying levels of discomfort, and the bikes don’t require much to temper it. The bikes tend to lean toward minimalism, typically sporting two bottle cage mounts as a maximum, as with the TCX Advanced.
The same is not true for gravel bikes, where designers are far more focused on utility rather than keeping things lightweight.
As a result, gravel bikes are – almost without exception – designed to be able to accommodate two bottle cage mounts inside the front triangle, one on the underside of the down tube, and a bento style top tube bag. Many will have additional bottle- or anything-cage mounts on the fork legs, and most will have some provision for rack and fender mounts. Enterprising bike designers will even consider things like routing for dynamo headlights and protective elements to reduce rub of bikepacking bags on the frame.
To use the Revolt Advanced as an example, there are three bottle cage mounts, a further mounting point on the fork, and mounts for fenders. And that’s at the minimal end of the spectrum for the category – many of its rivals will have top tube mounts, rack mounts and more.
All of those things add weight, and take away from the purity of a cyclocross bike. But they also add to the diversity of the bike significantly, making it a more appealing option for continent-crossing tourers, everyday commuters, and everyone in between. The capability that cyclocross bikes used to be lauded for has finally been realised with the arrival of the gravel bike.
At the very core of the discussion of the merits of each category is the geometry, with these measurements capable of playing a substantial role in the ride feel, comfort, and capability of each category.
Cyclocross bikes are far from homogenous, roughly splitting into European and North American schools of thought when it comes to geometry.
The more traditional European style tends to feature a higher bottom bracket drop of around 60 mm and, often, steeper angles in the front-end geometry. That’s a reflection of the sloppier nature of European CX courses, where a little extra pedalling clearance on off-camber sections and quagmires of mud can make the difference between a racer being able to pedal through it and having to dismount and run. Giant’s TCX leans toward this category.
The North American style, characterised by the likes of the Specialized Crux and the Cannondale SuperX, features a geometry that’s closer to the gravel space, with either lower bottom brackets, slacker head tube angles, or both.
But while CX bikes are more accommodating than road bikes, gravel bikes are far more diverse, ranging from extremely slack machines like the Evil Chamois Hagar, to dual suspension monsters like the Niner MCR9, to racey gravel bikes like the Parlee Chebacco and the Cervelo Aspero.
The Giant Revolt, for what it’s worth, sits somewhere in the middle.
Compared to road bikes, modern gravel bike geometry tends to lean towards a longer top tube paired with a shorter stem, a slacker head tube angle, a lower bottom bracket, and longer chain stays. All of that gives extra stability, reduced toe overlap at the front wheel with big tyres, and more space for frame bags in the main triangle. Because of the less technical nature of gravel riding compared to cyclocross, along with the differences in tyre volume, the rider is less likely to encounter pedal strike despite the lower bottom bracket height, while balancing the lower position of a 650b wheelset with larger volume tyres.
Despite fairly obvious similarities on a superficial level, there are wide ranging differences between cyclocross and gravel bikes. Across the two categories, you’re certain to run into geometry differences, variances in tyre clearance, and differing capacity to carry things. Some of these factors may determine how appropriate the bike is for your ambitions – others will be non-factors.
Wide-tyred drop bar bikes inevitably blur some lines. We’re fortunate to live in an era where the industry is taking steps to find space for a different type of riding beyond its road/CX racing comfort zone, and where riders have equipment that can accommodate this shift in attitude.