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Buyer's guide: Best gravel and adventure bikes 2020

Stu Bowers
19 Feb 2020

What makes a gravel bike? Cyclist gets the expert definition

How to choose the best gravel or adventure bike

First, decide what sort of riding you’re going to be doing. Tyres need to balance speed with grip and cushioning. The rowdier the riding you intend, the wider and more knobbly you’ll want the tyres. There are also two different wheel sizes to pick between: small and manoeuvrable 650b rims which are well suited to technical riding, and faster-rolling 700c wheels which are better on smoother surfaces. Look for how much clearance the frame and fork provide if you want to experiment later.

A bike’s geometry will often also tend to suit either thrashing around off-road or more traditional touring-style riding. Look at the figures given for the head angle and wheelbase. Slacker and longer will often indicate more stability at speed but can leave the handling slow on smoother surfaces.

Components make a big difference too. On long tours, you’ll want very easy gearing to help drag yourself up prolonged climbs. Wide bars will also keep you in control and provide space to fit a handlebar bag. However, go too wide and your upper body can end up acting like a big windsock.

Then there are materials to consider. Steel is popular for its comfortable ride, good looks, and durability. Carbon tends to be light and stiff but can wear or be damaged by bags straps or rock strikes. Aluminium is cheap and of middling weight, however, it can often impart a somewhat harsh ride on bumpy surfaces.

With all that in mind, here's in-depth introduction to gravel and adventure bike design - Plus a few of our favourite machines... 

The new breed...

It might seem that gravel riding is still in its infancy, but already the market is awash with this new breed of bike. And it is starting to splinter into distinct categories.

The definition of what constitutes gravel riding remains open to debate, and different brands are producing bikes to cope with a wide spectrum of road surfaces and conditions, from smooth tarmac to technical mountain bike trails.

So what exactly is a gravel bike, and how do you go about choosing the one that best suits your needs? Cyclist Off-Road talks to the brands and builders at the forefront of the gravel movement.

Cross over to gravel

‘A lot of the bikes look the same,’ says Dom Mason, founder of Mason Bikes. ‘But there are very subtle details that make a bike more suitable for a certain type of riding.’

It’s often assumed that a gravel bike is really no different to a cyclocross bike – both have drop handlebars and bigger tyres to cope with mud and grit – but they’re different bikes altogether.

‘People often buy cross bikes not necessarily to race cyclocross,’ Mason says. ‘They’re viewed as tough bikes that can fit big tyres and still have room for mudguards so are ideal for doing a bit of everything.

J.Laverack Grit from £4,455 & Ribble CGR 725 from £1,599

‘The reality is they’re actually not great for everything. A traditional cyclocross bike doesn’t have mounts for mudguards or rack mounts, and some don’t even have bottle cage bolts.

‘But more than that, they have evolved to be minimalist, for sprinting round a muddy field for a relatively short time. They don’t need to be comfortable and the frames have aggressive geometry, which doesn’t make them really suitable for much else.’

Stephanie Kaplan, road product manager at Specialized, agrees. ‘A cross bike should be designed 100% for performance. In cross you do a lot of stopping and starting, and acceleration is key.

‘You want short chainstays, a steep head tube angle to help you drive through the corners and a higher bottom bracket to give you pedal clearance over obstacles. But these aren’t desirable traits on a bike that you’d take on a long gravel ride.

‘Would you be fine on a cyclocross bike if you wanted to ride it as a gravel bike?’ Kaplan asks. ‘Sure. I’m not the sort of person who would say, “Hey, you can’t ride gravel if you don’t have a gravel bike,” but if we’re going to nit-pick, cross bikes aren’t designed for long rides or to be stable on rocky descents.

‘People are starting to understand that now. This new genre of bikes is being designed to be more specific to purpose. We have to accept the geometry has to change and more than anything else that has to do with tyre clearance,’ says Kaplan.

Vielo V+1UD from £5,299

‘Cross bikes only need to take a 33mm tyre. Most can take wider, but mainly because designers are thinking about mud clearance, not wider tyres. Simply cramming in bigger tyres will mess with the ride feel. Most gravel bikes will want a minimum of 42mm, and upwards of 48mm tyres are becoming common.

‘Straight away that means you can’t have such short chainstays, but nor does a gravel bike need to be so snappy in terms of how it feels. Most people want a more stable ride. We pushed for a lower bottom bracket height than most. Our BB drop is 85mm on the Diverge, while the average for a cross bike would be more like 68mm or 70mm.

‘The lower centre of gravity changes the way the bike feels. It’s like night and day for handling. The slacker head tube angle is also important, as are larger fork offsets to extend the wheelbase, both of which you wouldn’t want on a cyclocross bike.’

Stereo-atypical

‘I believe a gravel rider still wants to ride fast and cover a fair amount of ground, and probably still ride with friends in a group too,’ says Mason. ‘Gravel bikes should actually be more similar to what you might term “endurance road”: longer wheelbase, taller front end and a bit more compliance and comfort built in.

‘But then there’s still a demand to ride these bikes fast, so you don’t want the head tube to be too long. A lot of riders taking an interest in gravel riding come from a road background, so group riding is a big part of it.

‘It’s a different mindset to mountain biking in that regard. It’s about riding purposefully, to cover a reasonable distance at a decent speed.’

Canyon Grail CF SLX 8.0 Di2 £3,459

Less convinced of such a clear definition is Gerard Vroomen, co-founder of Open Cycle and designer of the 3T Exploro. ‘I’m not sure there is one definition of a gravel bike,’ he says. ‘To me, a gravel bike is the bike you ride on gravel.

‘That can be a cyclocross bike and that can also be a road bike. To me, the more interesting segment of the gravel market is to develop road bikes that can do much more. 

'What I think a capable gravel bike needs is geometry that’s well thought out enough so that when you put some road wheels in the bike and close your eyes – which I don’t recommend – it feels like a road bike.

‘But then throw on a different set of wheels with much bigger tyres and you can take that same bike almost anywhere, right up to moderate mountain bike trails. That would be my definition of a gravel bike. And I think that’s the kind of bike that makes a lot of sense for most people.’

‘I also think a gravel bike should make a better road bike for a lot of people than most road bikes,’ he adds. ‘I mean, most people don’t ride like pros, right? They would actually benefit from a longer wheelbase for stability, a slightly taller front end, those kinds of things that are factors of a gravel bike.

‘It also means you can run 30mm or 32mm tyres on the road, which inevitably means more grip for safer riding and being much more comfortable.’

Orro Terra C Ultegra £2,500

Gravel-o-meter

The terrain you ride and your expectations of what your bike needs to be capable of are likely to be influenced heavily by where you live. Gravel riding in the Highlands of Scotland is going to be quite unlike a gravel ride in the south of England, so your requirements are going to be very different.

‘We joked that we needed to develop a gravel gauge, like a gravel-o-meter, where you pick up gravel from the trails where you live and drop it through the gauge to help you figure out what kind of bike you need,’ says David Devine, road product director at Cannondale.

‘It was a joke, but actually it almost comes down to that. The spectrum is so broad. Some gravel roads are really smooth, well packed and there’s loads of traction so a 32mm pretty slick tyre will do you just fine. Others can be loose, with flints and rocks, and if you show up with less than a 40mm tyre you’re in trouble.’

Mason adds, ‘It seems there’s an arms race for brands to offer the biggest tyre clearances, to cram in the biggest possible tyre. A 32mm definitely isn’t big enough any more. People want to take these bikes beyond the capabilities of that.

‘Tyres of 40mm and bigger are now the norm. But just because there’s room for a big tyre doesn’t mean it’s a good idea to fit one. The bike has to be designed for that size of tyre.’

Vroomen agrees: ‘It’s not OK to just stick big tyres on any bike, even if there’s clearance. If you stick 45mm tyres on most cyclocross bikes you’ve screwed up the geometry. It’s very hard to make a bike that handles well with both 30mm and 45mm tyres.

‘The difference is so big that you change the trail and the bottom bracket becomes much higher off the ground. That’s detrimental to the performance of the bike, and that’s why swapping the wheel size avoids all that.’

Specialized Diverge Expert £4,250

Seismic changes

Vroomen’s original Open UP was a pioneering design, enabling wheels to be swapped between 650b and 700c sizes.

For anyone not familiar, 650b is slightly smaller, so that when a bigger volume tyre is fitted it will roughly equate to the same overall circumference as the larger 700c size with a narrower tyre.

This means the geometry changes Vroomen alluded to are neutralised, and done this way, substantially wider tyres can really transform the capabilities of a bike. 

'The beauty of gravel bikes that allow both 650b and 700c wheels is you can use a 700c tyre for more tarmac-oriented days, but then a quick swap to 650b can instantly transform the bike to give it a very different set of priorities,’ says Kaplan.

‘I’m not an n+1 kind of a guy,’ says Vroomen. ‘I don’t see a gravel bike as sitting next to my road bike in the garage. I see very much that I’m able to get that from one bike, especially now with more available gearing options. That has a lot of appeal.

‘It might mean needing two wheelsets to do everything, but that depends a lot on where you live. And, hey, if you can’t have two sets of wheels, those tyre knobs on asphalt don’t really slow you down as much as you’d think. It’s surprising.

‘In my opinion, gravel bikes shouldn’t be confused with the kind of bike I’d use to go trekking for three months across Mongolia,’ adds Vroomen. ‘That’s cool as well, but to me that’s a completely different segment. I’d call that a globetrotting bike, or whatever. That’s a whole different conversation.’

‘A gravel bike shouldn’t be confused with a hardtail mountain bike with drop bars either,’ says Mason. ‘Some people suggest it is, but it’s not.

Open New UP Frame £2,900

‘Mountain bike geometry is longer and slacker again, plus mountain bikes only really come in three sizes. Gravel bikes are sized like road bikes and fit is still an important aspect of set-up. It’s not as freeform as modern mountain bikes.’

Kaplan adds, ‘I think there will be a lot of people trying to adapt the bikes they have to start with, but when they see the potential this type of riding has to offer they will almost certainly be looking to buy something more specific.

‘It’s easier to backwards-convert a gravel bike to be capable on the road than to convert a road bike to be capable off-road. A gravel bike with 30mm road tyres can still feel capable on the road. The frame weights now are not so different. Our Diverge frame weighs 880g. Not so long ago that was considered incredibly light for a road frame.

'A gravel bike can definitely still be a performance bike, and we are starting to see that with ultra-endurance cross-continent races like the Transcontinental,’ she concludes.

Vroomen has the final word: ‘Five years ago I said that in 10 years gravel will be a bigger segment than road. These bikes should be capable of doing everything most people want to do on bikes. It’s not a fad.

‘This market will only grow in size, because for different people and for different reasons everything will converge on this type of bike.’

Read our guide to the best full suspension mountain bikes and best mountain bike tyres