Gravel bike setup: how to choose the right gearing, wheel size, tyres and more

Gravel bikes are extremely versatile, but that also means you have a wide range of setup options. Here's everything you need to know

Gravel riding on a farm track

Every bike brand worth its salt has a gravel bike in its range, but there’s a vast array of different spec choices and setup options out there.

Advertisement

Some bikes are geared towards fast rides on and off-road, while others are set up to carry luggage on long-haul adventures, well off the beaten track.

There’s a wide range of gravel bike geometry to reflect this, with gravel race bikes configured more like road race bikes, while bikepacking bikes will be designed for more relaxed handling when loaded.

Deciding on the best gravel bike for your needs partly depends on your requirements as a rider – where and how you ride – and its specific configuration, from gearing and wheel sizes, to tyre width and finishing kit.

What are the spec options to look out for? And what components can you tweak to adapt your gravel bike so it best suits your type of riding?

Whether you’re on the lookout for a new gravel bike, or you’re looking to upgrade your current ride, we’ve demystified the intricacies of gravel bike setup to help you make the right decision.

You can use the links below to jump to the section you need – or read on for our ultimate guide to gravel bike setup.

Gravel bike groupsets

SRAM’s new XPLR cassette offers a 440 per cent range with sprockets ranging from 10-44t.
Andy Lloyd / Immediate Media

Acknowledging the surge in popularity of gravel riding, all of the major groupset manufacturers have released gravel-specific groupsets: Shimano GRX, Campagnolo Ekar and, most recently, SRAM XPLR.

All three share wider gear ranges than equivalent road bike groupsets, although they each feature different numbers of gears, or ‘speeds’ on the cassette. Shimano GRX has options for 10-speed or 11-speed setups, SRAM XPLR uses a 12-speed cassette, while Campagnolo Ekar pushes on further to 13 sprockets.

Besides gearing, these gravel bike groupsets have been designed to contend with the increased braking demands of gravel riding. Shimano’s GRX brakes take Servo Wave tech from the company’s mountain bike groupsets to increase braking power and modulation for steeper, more technical descents.

As with road and MTB groupsets, you can choose between mechanical or electronic shifting with Shimano and SRAM options. Campagnolo Ekar is mechanical only.

Gravel bike gearing

A gravel bike will typically offer lower gearing than a road bike.
Irmo Keizer / Shimano

A few years ago, many gravel bikes came fitted with a 50/34t compact chainset commonly seen on road bikes, along with a fairly narrow-range cassette.

That’s still a good option if most of your riding is a mix of tarmac and gentle off-road trails, and you’re not expecting to carry a lot of kit.

However, once you hit more loose, steep road and trail surfaces, you’ll need easier gear options to help you keep the pedals turning.

How low can you go?

If your riding includes lots of off-road climbing, low gears are a good idea.
Felix Smith / Immediate Media

With that in mind, the trend nowadays is towards much lower gearing for gravel bikes. Many new gravel bikes will have gears that give you the lowest ratios of 1:1 or below. That should enable you to climb steep, loose off-road ascents when unladen, and also gives you more range to load up your gravel bike for multi-day bikepacking trips.

SRAM has a range of 12-speed wireless gearing options designed for off-road riding. Its XPLR groupsets offer gravel-appropriate gearing at the Red, Force and Rival levels, with a single-chainring drivetrain (see below) matched to a 10-44t cassette and an appropriate rear derailleur.

Campagnolo joined the gravel groupset party with the launch of Ekar.
Matthew Loveridge / Immediate Media

The downside of lower gearing is you may run out of top-end gears if you’re descending on tarmac, though the reality is you’ll normally have plenty of gears for fast riding.

It’s worth considering the type of riding you’re expecting to do when choosing a gravel bike or a new groupset.

Chainring sizes

Shimano’s gravel-specific GRX groupsets give you a choice of 48/31t or 46/30t double chainsets.
Matthew Loveridge / Immediate Media

The shift to lower gear ratios is driven by changes at both ends of the drivetrain.

At the front, there’s a trend towards smaller chainrings, with super-compact chainsets (also known as sub-compact) increasingly specced, where the chainring sizes are smaller than a standard 50/34t road compact.

These are available in an array of smaller size combos: Shimano’s gravel-specific GRX groupsets give you a choice of 48/31t or 46/30t double chainsets, and a growing number of aftermarket suppliers, including the likes of FSA, Rotor and Praxis, sell gravel chainsets with similar-sized rings.

SRAM’s XPLR chainrings are available from 38-46t and Campagnolo Ekar chainrings range from 38-44t.

As well as lower ratios, a smaller chainring means bike designers can more easily add clearance for wider tyres, supporting another trend in gravel bike design.

The SRAM Wide two-ring gravel chainset at Force and Rival levels offers a 43/30t chainset with its chainline shifted 5mm to the right compared to its standard chainsets. This means that there’s more space around the chainstays for wider tyres and the small rings make for plenty of low-ratio gearing.

Cassette options

The rise of gravel riding means much bigger cassettes are now available. Gravel-specific rear derailleurs normally have a switchable clutch to keep the chain in check.
Matthew Loveridge / Immediate Media

Meanwhile, on the back of the bike, the latest rear derailleurs can handle much larger cassettes, once again ensuring a wider range of gears for off-road riding and bikepacking.

Whereas older rear derailleurs designed for road bikes might just about squeeze in a 30-tooth largest sprocket, many modern road rear mechs can handle 34 teeth, giving you a couple of easier gears for climbing. SRAM 12-speed derailleurs can handle a 10-36t cassette with two chainrings.

Swap to a gravel-specific derailleur and you can typically head up to around 42 teeth, although these wide-range derailleurs are designed to work with single-ring groupsets (which we’ll come on to), rather than double chainsets.

In terms of top-end speed, Shimano’s 11-speed cassettes start at 11 teeth, but SRAM has options with 10 teeth on the smallest sprocket, and Campagnolo’s Ekar groupset goes smaller still with a nine-tooth sprocket.

Campag’s Ekar cassette goes down to a tiny nine-tooth smallest sprocket.
Matthew Loveridge / Immediate Media

Ten-tooth cassettes only fit SRAM’s XDR freehub body, rather than the standard Shimano/SRAM design, and Campagnolo Ekar has its own N3W freehub.

To keep the chain taut over such wide ranges and aid chain retention, gravel-specific rear derailleurs, including Shimano GRX, SRAM XPLR and Campagnolo Ekar, will typically incorporate a clutch.

The clutch is always engaged in Campagnolo and SRAM’s designs but there’s a lever on Shimano’s GRX and Ultegra RX derailleurs to let you release it when you’re riding on smoother surfaces.

There’s a marginal decrease in drivetrain friction if the clutch is disengaged, but most helpfully it makes removing the rear wheel easier.

1x or 2x?

Taking the lead from the mountain biking world, we’ve seen gravel bike groupsets heading increasingly towards a single-chainring setup, paired with a very wide-range cassette, as opposed to a double chainset. SRAM and Shimano both offer single-ring options, while Campagnolo Ekar is single-ring only.

With a 1x groupset (as a single-chainring setup is known), you save a little weight by dispensing with the front derailleur, plus there’s less to go wrong and less chance of mud build-up. They are also designed to keep the chain in place and running smoothly when you’re riding over bumpy ground.

SRAM’s Force eTap AXS Wide gearing is designed for gravel bikes.
John Watson / SRAM

On the minus side, there are sometimes fewer gear options covering roughly the same gear range, so jumps between gears are larger.

Gravel riders who spend a fair amount of time on the road, or covering ground quickly, might find the extra top-end range of a double chainset useful. Plus, the additional weight of a larger cassette often negates the weight savings from losing the front derailleur.

That said, once you take account of overlaps in ratios between the large and small chainrings in a two-ring setup, and unusable combinations at the high and low ends of the cassette, the actual number of unique gears isn’t that different.

Campagnolo has also sought to address this by moving to 13 speeds with Ekar, allowing for a wide-ranging cassette with smaller gaps between sprockets.

If you’re likely to ride your gravel bike on the road as much as you are off-road, you might appreciate a 2x drivetrain.
Joseph Branston

A single-ring setup means you can access all gears sequentially too, rather than needing to swap chainrings to access your higher or lower ranges; no more cross-chaining.

Because the chain doesn’t have to jump between rings, single-ring chainsets have deeper teeth on the chainring to help keep the chain in place. Single chainrings usually have alternating wide and narrow teeth to match the different widths of the chain links, again to improve chain retention over uneven surfaces.

Ultimately, deciding between a single-ring and a double-ring setup depends on the riding you’re planning, and your preferred groupset brand.

If you’re wanting to ride mainly fast on the road and on smoother terrain, a double-ring chainset could give you a few more high-end ratios and smaller jumps between gears, while if you’re looking to tackle harder terrain, you may appreciate the chain retention benefits and simplicity of a single ring.

Mullet builds

SRAM allows you to mix and match its road and mountain bike components, meaning you can use a super-wide cassette on your gravel bike, as pictured here.
Russell Burton / Immediate Media

Want even lower gears? So-called ‘mullet’ builds mix a road chainset and shifters with a mountain bike rear derailleur and cassette for an ultra-low gear range.

Using Shimano’s electronic Di2 components, you can pair GRX shifters with an XTR or Deore XT Di2 MTB rear derailleur. Both MTB derailleurs can handle an 11-42t cassette in double-chainring configuration, or 11-46t with a single chainring.

It’s an option also promoted by SRAM with its AXS 12-speed wireless electronic components. Here, the AXS Eagle MTB rear derailleur is designed to work with an Eagle 10-52t cassette, giving really low ratios when paired, say, with a 42-tooth chainring.

With the release of SRAM XPLR, we might see fewer of these mullet builds though, because you can now run a 10-44t cassette with a 1x chainring, bridging the gap between MTB Eagle gearing and SRAM Wide.

If you’re really into mix-and-match drivetrains, there are a host of brands, such as Wolf Tooth Components and Garbaruk, that make parts to let you do pretty much whatever you like.

Gravel bike pedals

Pedal choice is another area where there are lots of options.

The best gravel bike pedals are usually considered to be SPD-style two-bolt pedals. These have two points of entry for easy clipping in (or four for the Crankbrothers Eggbeater pedals) and the recessed cleats and lugged soles of gravel bike shoes make walking with the bike a lot easier than three-bolt shoes.

A minimalist SPD pedal will shed dirt easily but may not give the most stable pedalling platform.
Katherine Moore / Our Media

SPD pedals often have minimalist skeleton designs. This helps with mud shedding, but results in a small contact area between your pedals and your shoes. Depending on how stiff your shoes are, this can sometimes be felt through the sole and may reduce pedalling efficiency.

So, a pedal with a platform can also be a good option because it adds to the contact area between the pedal and the foot. It also makes pedalling unclipped easier, if you’re riding tricky terrain or trying to restart on a steep climb.

Some pro gravel racers use road bike pedals and shoes.
Wilier

Having said that, some gravel racing pro riders will ride with three-bolt road bike pedals, because they rarely dismount.

The other alternative is flat pedals. As with mountain bike riders, some gravel riders prefer these for the ability to remount quickly, change their position easily and dab a foot in a turn or a skid.

Wheel size

650b or 700c wheels? Both offer advantages and disadvantages, depending on your riding style.
Irmo Keizer / Shimano

Over the last few years, many bike brands have developed their own designs for gravel wheels too.

The usual 700c road wheels continue to be popular, but there’s an increasing range of gravel bike wheels, which typically have wider rims than a road-going wheel to provide better support for wider gravel tyres. Road rims are following fast in their wake and getting wider too.

Gravel bikes are invariably designed with disc brakes, and rims are almost always tubeless-ready, except for some cases where tight budgets mean non-tubeless compatible wheels are specced. The puncture protection afforded by the sealant in a tubeless tyre is a godsend when riding over broken surfaces and thorny debris.

Many gravel wheels are supplied as ‘tubeless ready’, which means they’re already fitted with tubeless rim tape and supplied with tubeless valves.

Hookless rims, where there is no lip to the rim edge, are increasingly common. Hookless rims have been popular in mountain biking for some time, and are gaining prominence on the road and in the gravel scene too.

Alongside 700c wheels, many gravel bikes come with the option to fit 650b wheelsets. The smaller size – equivalent to 27.5in mountain bike wheels – lets you fit even wider tyres in your frame, with greater volume.

You don’t need gravel-specific wheels, but they are typically available in both 650b and 700c sizes, and have a wide internal rim width that’s well suited to plump gravel tyres.
David Caudery / Immediate Media

That adds comfort to the ride, as well as increasing grip on off-road terrain and letting you run even lower tyre pressures. With a large tyre, the rolling circumference of a 650b wheel is similar to a 700c with a narrow tyre, so gearing and handling should end up similar.

Rather like the single/double chainset choice above, which wheel size works for you depends on your objectives and what you want from your gravel bike.

For a faster ride on road and light gravel, you’ll probably want to stick to 700c wheels with narrower tyres of 40mm or less. If you’re planning to head for more difficult terrain, you’ll appreciate the grip and cushioning offered by wider tyres on 650b, although that might be at the expense of speed on tarmac.

If your gravel bike has the clearance, a set of each wheel size could give you the best of both worlds, enabling you to swap between them depending on the ride.

Tyre choice

The right tyre choice for your bike will depend significantly on the terrain and conditions you typically encounter.
Irmo Keizer / Shimano

Fitting the best gravel tyres for the riding you’re doing is another key decision for your gravel bike setup.

In fact, changing the tyres on a gravel bike from the stock build can unleash the true potential of your machine, either significantly improving its ability off-road or adding a turn of road speed.

With gravel bikes used across such a wide range of terrain, it’s one area where you can easily change how your bike performs. We’d recommend tubeless tyres for gravel riding.

Gravel tyre width

Once you’ve settled on 700c or 650b wheels, tyre choice will largely be determined by tread pattern and width. If off-road grip and stability are important, look for wider tyres with a more aggressive tread pattern; if you’re more likely to be riding on the road or dry, hardpack gravel, a narrower, slicker tyre will likely be more suitable.

700c gravel tyres are typically around 40mm wide, although you can get tyres that are wider or quite a bit narrower too. Typical widths are 35mm, 40mm, 42mm or 45mm. Have a look at this article, where we rode three different-width gravel tyres from Maxxis, for an idea of the effect of tyre width on your ride.

How wide you go will depend largely on the terrain you ride and your frameset’s clearance. If you live somewhere with a wet climate, it’s a good idea to leave some room for mud too.

Gravel tyre tread pattern

Gravel riding can take in a wide range of surfaces.
Russell Burton / Immediate Media

How muddy it is will also influence your tyre choice. In dry conditions and on finer gravel surfaces, you can usually get away with a file tread such as the Panaracer GravelKing SK or a semi-slick design, with a smooth centre, such as the WTB Byway.

The low-profile tread makes for fast rolling on tarmac, while there’s still enough grip from the side lugs to keep you upright and moving on looser surfaces.

If it’s wet or muddy, you’ll need something with more grip from a knobbly tread pattern. Schwalbe’s G-One range goes from the small knobs of the G-One Speed through to the G-One Ultrabite, while Continental offers the Terra Speed and Terra Trail for varying conditions.

There’s a whole range of gravel tyres from many manufacturers, designed for different terrain.

In wet or muddy conditions, large widely-spaced knobs can improve grip and also help to shed mud. A tighter-packed tread won’t work as well in wet conditions but will usually roll faster on tarmac or more hard-packed gravel surfaces.

For very muddy conditions, some cyclocross tyres are a good option too. At 32mm to 35mm wide (the UCI limit is 33mm for racing), they’re typically narrower than gravel tyres.

This can help with grip because – in theory at least – the tyre can cut into the mud and down into harder surfaces, where a wider gravel tyre might float over it or clog.

The narrower tyre also means you’re less likely to get mud clogging your frame – handy if clearances are tight, which they often are on cyclocross bikes or older gravel bikes.

However, as cyclocross tyres are typically designed for use on grass and mud, they may not be as durable over rockier, more rugged terrain as gravel tyres. Look out for more durable casings here if they are on offer.

If you’re running 650b tyres, again there’s a range of gravel options, with different tread patterns available.

650b gravel tyres are typically (but not always) focused on high-volume options, so you’re more likely to find tyres with more aggressive tread patterns and in large sizes. These tend to start out at 40mm and head up to 50mm wide or more.

27.5in mountain bike tyres are also an option and may offer a deeper tread for more grip. Confusingly, MTB tyre size is often designated in inches rather than millimetres. You’ll want to check you’ve got clearance in your frame for some of the wider options.

Tyre pressure

Tyre pressure is particularly important on a gravel bike. Luckily, with a wide range of tyres – including tubeless options – there’s plenty of room for experimentation.
Irmo Keizer / Shimano

Along with tread pattern and width, tyre pressure is a big determinant of how your gravel bike will handle.

The large air volume of wider tyres means you can drop your pressure, giving you better traction, potentially lower rolling resistance and a more comfortable ride.

Giving a rough starting point for tyre pressure is a tricky business because it’s so dependent on riding style, rider weight and terrain. However, as a guide, we would recommend around 40psi for a 40mm-wide 700c tyre, though you can usually drop below this.

With a wide 650b tyre – something in the 45mm+ range – 35psi is a good starting point. Check out an online tyre pressure calculator like this one from SRAM for a more precise guide, which takes many more factors into account.

The right tyre pressure for your gravel bike will depend on a number of factors, including tyre width, rider weight and terrain.
Felix Smith / Immediate Media

It’s worth experimenting with tyre pressure to see what works for your tyre choice and where you ride. Too high and you’ll get bounced around and lose grip, while too low a pressure may result in sloppy handling and extra pedalling effort, as the tyre squirms on the rim.

Tyre pressure that’s too low may also result in you bottoming out on the rim, if you’re riding on uneven surfaces. If you’re using inner tubes that might result in a pinch flat, but with a tubeless tyre it’s less of a problem – though it’s still possible to pinch flat a tyre. Yikes!

Experiment, take notes and think about investing in a digital pressure gauge. This will make future fiddling far easier, more accurate and, critically, repeatable.

Tyre inserts are another option to up your protection and there are a few designed specifically for gravel riding, such as the Vittoria Air Liner Gravel. They enable you to run lower tyre pressures with less risk of bottoming out, tyre squirm or burping, where the tyre becomes disconnected from the rim and loses air.

Finishing kit

Flared handlebars can offer more control off-road.
Irmo Keizer / Shimanoa

Some gravel bikes come with flared handlebars, which are wider in the drops than at the tops. That means you’ve got a bit more control when descending off-road, thanks to the wider position.

You also get a little more real estate between the levers for bikepacking bags on the front. Some flared bars do cause the brake levers to sit at an angle, though; the ergonomics can feel a bit awkward with a very wide flare.

Another gravel bike trend borrowed from mountain bikes is towards shorter stems. Whereas a road bike might have a 100mm stem, on a gravel bike this might drop to 70 or 80mm. That again helps with steering on awkward trails, as well as reducing the effective reach to the bars.

Some gravel bikes are following mountain bikes with a move towards shorter stems.
Jack Luke / Immediate Media

You’ll want a comfortable saddle too. This is totally personal, though you should be mindful that what works for you on your road bike or mountain bike might not also work on a gravel bike, due to the altered body positioning.

Gravel bike dropper seatposts

A growing number of gravel bikes are specced with dropper posts too, albeit the number is still limited.

Some frames, however, will have ports to enable you to route the cable for an aftermarket dropper post internally, if you choose to upgrade.