Updated: February 17, 2020
Between rapid technical innovation, wildly popular events like Unbound Gravel and Belgian Waffle Ride, and the growing ranks of pro riders, gravel cycling is hot right now. Gravel’s growth has outpaced the rest of the cycling world in the last few years. This has given average cyclists like us a wonderful array of gravel bikes for new adventures — bikes that didn’t exist only five years ago.
However, if you aren’t dutifully following every product release as bike companies jump on the gravel bandwagon, it can be hard to keep up and know which gravel bike is right for you.
Lucky for you, we keep track of all this fast-paced product development, and The Pro’s Closet sells Certified Pre-Owned gravel bikes from literally every manufacturer. So let’s help you find the perfect bike to leave the pavement behind. Here are five key considerations when shopping for a gravel bike.
1. Gravel bike vs. road bike — which should I ride?
Old-timers might gripe that gravel cycling is nothing new, and they’d be right. Before wide tires and drop bars joined in blissful matrimony, we hacked along with narrow, 26mm slick tires on dirt roads whenever we felt adventurous. So should you just muddle through with a road bike?
Sure! If you’re a competent bike-handler who primarily rides pavement, and your dirt excursions are mostly smooth, well-traveled roads, modern road bikes won’t hold you back much. Endurance road bikes are especially suited to switch-hit because they offer more compliance features, more upright positions, disc brakes, and clearance for tires as wide as 32mm. Plus, these bikes won’t slow you down on spirited group rides or even races.
Road bikes do have limitations, though. If speed isn’t a top priority, you might prefer the added comfort and control of a true gravel bike that fits tires in the range of 40-45mm (more on tires in a minute). Plus, a dedicated gravel rig will have frame mounts for bags if you dabble in bikepacking or just want to carry a ton of snacks. And above all, if your riding takes you onto more challenging terrain — singletrack, jeep roads, sandy washes, or mud — the stable geometry and confident handling of a gravel bike will win out over a road bike.
2. Gravel bike sizing
Gravel and cyclocross bikes are similar to road bikes in terms of fit. Sizing is often numerical, in centimeters, measured from the center of the bottom bracket to the top of the seatpost clamp. Top tube length will be one of the key measurements to consider. A gravel bike likely will have a taller head tube than a comparable road bike, to provide a more upright position.
If you have a drop-bar bike already, that’s a good starting point to find the correct size. If a friend has a bike with similar measurements, it’s helpful to ride it a little to get a feel for the fit. Unlike road bikes, gravel bikes are typically designed to fit with shorter stems, often 80-100mm, so it’s best to avoid buying a bike that’s too small in hopes of making it fit with an inordinately long stem, and vice-versa with a too-big frame.
3. Gravel wheel options
In terms of wheel sizing, gravel bikes take after their mountain bike brethren. Unlike road bikes, which stick to 700c wheels, gravel bikes are available in both 700c and smaller 650b sizes.
If speed is a priority and you don’t need particularly wide, high-volume tires, 700c is almost always preferred. If you plan on riding rough trails, 650b wheels allow you to fit bigger tires — often up to 50mm — giving you more traction, comfort, and leeway to run lower pressures.
Many gravel bikes are designed to fit either wheel size, giving you the option to change it up if you prefer one over the other.
4. Gravel bike tires
Generally, gravel tires range from 35-45mm in width, other than a few exceptions like the thick 650b options we just covered. Most riders settle on something near 40mm for versatility, but to shave weight and rolling resistance, narrower tires are an option.
Whenever possible, opt for tubeless gravel tires. Nearly every modern gravel tire and wheel is available in a tubeless-ready configuration. The extra effort needed to set up tubeless tires with sealant like Stan’s NoTubes or Orange Seal will pay off when it comes to performance and peace of mind. Tubeless lets you run lower tire pressure for better traction and comfort, without the risk of pinch-flatting a tire. The sealant often fixes any little nicks or cuts from sharp gravel. Once you ride tubeless, you’ll never go back.
Other considerations when tire shopping include tread pattern and puncture protection. The former depends on your local conditions and personal preferences. Loose dirt and rocks often necessitate a knobby tread pattern that’s almost like a mini mountain bike tire. Slick tread patterns offer better efficiency for pavement and buffed-out dirt roads. Tires with additional puncture protection are wise if your gravel roads are chunky with sharp stones, like the flint gravel near Emporia, Kansas, home to Unbound Gravel. The built-in puncture-resistant lining helps minimize cuts but adds weight. If you’re miles away from civilization, the reliability of heavy tires might outweigh the performance sacrificed.
Read more: Beginner's guide to tubeless tires
5. Gravel bike gearing options
It all started with mountain bikes. For eons, cyclists were content to rely on front derailleurs and multiple chainrings for wider gear range. But over the last 10 years or so, mountain bikes led the charge toward single-chainring drivetrains. Now gravel cyclists face a decision between 1x or 2x drivetrains, the new MTB-inspired configuration vs. the traditional road technology. Some adventurous riders even go for singlespeed drivetrains for greater simplicity.
Fortunately, we wrote an entire article outlining the benefits and drawbacks of each option. The short explanation is that gravel bike gearing depends on your riding terrain. Many factors come into play: the steepness of your climbs, your fitness level, whether you’re racing, concerns about chain security, and even your general proclivity for simplicity. As is the case with all of this new gravel bike technology, we have tons of options. The key is finding what works best for you.
Read more: 1x vs. 2x gravel bike drivetrains
Read on for a deeper dive on all the factors to consider when buying a gravel or cyclocross bike.
Cyclocross and Gravel bikes are drop-bar bikes designed to handle off-road riding. These bikes strike a balance between the efficiency of road bikes and the capability of mountain bikes.
For the purpose of simplicity, this guide discusses both gravel and cyclocross bikes together. There is a significant amount of crossover and a large number of riders will use one bike to satisfy both styles of riding. Nowadays, some brands are designing cyclocross bikes that are capable enough for gravel riding.
Here are the key differences between a bike that’s purely built for gravel and one that’s meant for cyclocross.
Gravel frames vs. cyclocross frames
Gravel frames are designed for long-distance riding, necessitating geometry that is stable and well-mannered. Usually, this means a slacker head tube angle, longer wheelbase, lower bottom bracket, and taller stack. Plus, gravel frames often afford more tire clearance, additional mounts for bottles and bags, and sometimes even incorporate aerodynamic features for battling across the windswept prairie.
Cyclocross frames are designed for short, high-intensity races where bike-handling can be the difference between winning and losing. They are made to respond to rapid rider inputs, meaning the overall feel is fast, bordering on twitchy. Cyclocross frames are everything that gravel frames are not: steeper angles, shorter wheelbase, lower stack — all in the name of handling quickness and precision. Cyclocross top tubes are often horizontal so the bike is easier to shoulder while running.
Gravel tires vs. cyclocross tires
Most pure cyclocross tires are 33mm wide, in part because that conforms with the rules of cyclocross racing. (I know, it sounds silly, but so does running around in the mud with a bike on your shoulder.) As mentioned above, most gravel tires are about 40mm wide.
Gravel tires are typically built to be more durable for flat prevention, while cyclocross tires are meant to be lighter and suppler for higher performance usage. Serious cyclocross racers often choose tubular tires for better traction and an ephemerally blissful ride feel. These glue-on tires are a maintenance headache and difficult to repair mid-ride, so you wouldn’t want tubulars for gravel riding.
Gravel gearing vs. cyclocross gearing
Given that ‘cross racing is fast and furious, the gearing is more akin to a road bike with tight jumps between gears. Often, cyclocross bikes also have single-chainring drivetrains, further limiting gear range but ensuring chain security on bumpy race tracks.
Gravel bikes usually rely on a wide gearing range to handle everything from fast, flat races to grinding climbs up forgotten forest service roads. However, like cyclocross bikes, gravel bikes need reliable chain security, so you’ll see similar features between the two, such as clutch rear derailleurs and narrow/wide chainrings on 1x drivetrains.
Your choice of frame material will usually come down to personal preference, price, and the type of riding you like. The integrity of a bike’s frame is paramount to its value and safety, so it is essential to check for structural damage, cracks, and other potential issues. Carbon often receives the most scrutiny, but all frame materials can fail and should be carefully inspected when purchasing a used cyclocross or gravel bike.
If you choose a pre-owned or Certified Pre-Owned bike from The Pro’s Closet, they are all professionally inspected by one of our full-time bike mechanics and guaranteed to be in perfect working order. They are also professionally packed and shipped so they arrive safely.
Aluminum is often the most affordable frame material. When comparing two similar bikes, it will usually be heavier than carbon, but it’s also less expensive and, in some ways, slightly more durable. This makes it a good option for budget-minded riders and amateur 'cross racers who will abuse their bikes. Though aluminum has a reputation for being extremely stiff, many newer aluminum bikes can provide a ride feel nearly as good as some of their more expensive carbon counterparts.
For more information, check out our detailed Carbon vs. Aluminum article.
Carbon is the latest and greatest material in cycling, and most high-end bikes will use it in some form. It can be used to make frames that are lightweight, stiff, and responsive, and it can also be shaped into special aerodynamic shapes. Across all cycling disciplines, high-end race bikes are almost always carbon. Carbon can also be engineered to have greater compliance in key areas for added comfort. This generally comes at a price as carbon frames are typically more expensive.
For more information, check out our detailed Carbon vs Aluminum article.
Steel is the classic frame material, used since the bicycle’s inception. It’s revered by many for its supple ride quality and durability. A steel frame will likely last a lifetime if it's maintained correctly. Steel's rugged nature makes it a popular option for adventure riding and long-distance off-road touring. It is often slightly heavier than other materials, but plenty of riders prefer it simply for the feel, durability, and the classic good looks.
Like steel, titanium is a classic and rugged frame material. It has a supple ride quality similar to steel, but is much lighter, and has great durability thanks to its high strength and resistance to oxidation. The trade-off is a much higher price tag. Few big brands offer titanium frames, so it is often limited to smaller boutique and custom builders.
The three most common drivetrain manufacturers are Shimano, SRAM, and Campagnolo. All three brands offer groups with hydraulic disc brakes that are compatible with modern disc brake-equipped 'cross and gravel bikes.
Your choice will largely come down to personal preference and budget. Entry-level drivetrains will generally be cheaper, but feel less refined and are heavier. As you become more experienced and competitive (and pickier), high-end components will feel like a greater necessity.
Basic Component Hierarchy
Tiagra / GRX 400
105 / GRX 600
Ultegra / GRX 800 / Di2
Force 1 / eTap AXS
Dura-Ace / Di2
Red / eTap AXS
All three major component manufacturers offer groupsets that are gravel specific.
Shimano's GRX groups come in three levels: RX400, RX600, and RX800. Depending on the level, they each use a different crankset and cassettes and chains from their comparable road groups. RX400 is 10-speed, while RX600 and RX800 are 11-speed. They are available in 1x and 2x options, as well as with Di2 electronic shifting.
SRAM offers 1x specific versions of its Apex, Rival, and Force groups for gravel and cyclocross. These use a wide-range, clutched derailleur for off-road performance. SRAM's new Force and Red eTap AXS wireless electronic groups are also a good high-end option with the new Orbit damper rear derailleurs and X-Range gearing.
Campagnolo's Ekar groupset is the first gravel-specific offering from the Italian brand. It is a 13-speed 1x specific drivetrain with wide-range.
Each of the three major drivetrain manufacturers also has electronic shifting options. These are generally reserved for their higher-end offerings. Shimano's electronic groups are designated as "Di2" and SRAM as "eTap AXS."
Electronic groups are more expensive than tradition mechanical groups but have a few benefits. They provide crisp, fast shifting, require little tuning, and many new groups have a smartphone app for updates and customization. Batteries will generally last months without recharging.
Read more: Do you need electronic shifting?
In cyclocross, 46/36t has been the traditional 2x chainring combo paired with an 11-28t cassette. With a 1x drivetrain, a cyclocross racer might run a 40t or 42t chainring paired with a wide-range 11-32t or 11-36t cassette. This will provide enough gears for most racers on standard 'cross courses.
Gravel riders often need more gear range for a greater variety of off-road terrain. Chainring combos like 48/31t or 46/30t for 2x set-ups are common and provide a big top-gear to prevent getting "spun-out" and a low gear for steep climbs. !x set-ups generally use a wide-range cassette originally designed for mountain bikes like 10-42t, 11-42t, and 10-50t with a chainring ranging from 36t to 46t. One 1x set-ups chainring size is the main part riders change depending on whether they need a harder top-gear for fast flat roads or an easier bottom gear for hard climbs.
Brakes come in two styles: rim and disc. Rim brakes have been the standard almost since the inception of the modern bicycle. Disc brakes, however, are now the dominant technology for cyclocross and gravel as they provide lots of advantages and few drawbacks.
Cyclocross bikes have used the cantilever brake for decades. These differ from the calipers used on road bikes as cantilevers use two separate braking arms on their own pivots rather than a caliper with the two arms connected by pivots. This affords more tire clearance. Cantilevers are light, simple, and easy to maintain. Cantilever rim brakes are generally found on older cyclocross bikes.
Disc brakes entered cycling from mountain biking and are now the standard for 'cross and gravel bikes. Disc brakes are more powerful than rim brakes and are less affected by grit, mud, and wet conditions. They also provide increased modulation which is great for maximizing braking traction on loose surfaces and greater resistance to heat which is beneficial on fast and long descents.
Hydraulic disc brakes are the most common. They require the use of hydraulic fluid in the form of mineral oil or DOT brake fluid and need to be periodically bled to maintain performance. Some bikes use mechanical disc brakes. These use a traditional cable to activate the caliper. They are easier to maintain, but provide less power than hydraulic brakes.
As gravel riding has evolved, components changed to suit it. There are now many parts offered on gravel bikes and as aftermarket upgrades that improve the experience of gravel riding.
As riders have sought greater confidence and control in off-road situations, flared drop bars have become popular. The lower drop portion of these bars flares outward so that they are wider at the drops than at the hoods. This wider stance provides more control when riding singletrack and technical descents.
Different bars have different amounts of flare (measured in degrees). In general, more adventure-style gravel riding will benefit from an increased flare. Riders doing more fast group rides and races may prefer traditional bars as they place you in a more aerodynamic position.
In the search for more comfort and traction, some bike companies have turned to suspension. Gravel suspension forks are similar in technology and spirit to mountain bike forks but are designed specifically for the demands of gravel riding. This means they are lighter and have less travel than a mountain bike fork.
The Lauf Grit and Cannondale Lefty Oliver are two examples of minimalist gravel suspension fork technology. The Lauf uses glassfiber springs that provide 30mm of travel and, unlike air forks, requires no maintenance. The Lefty Oliver is a single-sided air fork, similar to Cannondale's XC mountain bike forks, but with a carbon upper and 30mm of travel. This fork is standard equipment on the Cannondale Slate which we reviewed here.
There are a few other gravel suspension fork options available or in development. In the future, there are sure to be plenty more.
Dropper posts are a rare sight on gravel bikes but some riders swear by them. A dropper is a hydraulic- or spring-actuated seatpost that is height-adjustable. These posts are usually controlled by a remote at the handlebar which allows a rider to instantaneously lower their saddle. They aren't necessary for most gravel riding, but if you're interested in making your bike more capable, it's worth considering.
For optimal pedaling, you need proper leg extension for power and efficiency. A saddle positioned for optimal pedaling, however, is generally too high for some riders to descend comfortably on steep or technical terrain. A lowered saddle is out of the way, allowing you to easily maneuver the bike around beneath you. Droppers work best for riders who plan to descend aggressively on their bikes and don't mind carrying the extra weight.
Dropper posts take a lot of abuse. Used droppers and even some new ones often have a poor reputation for reliability. If any sag, stiction, leakage, or other issues are present, then a dropper will need to be serviced or replaced. The Pro's Closet inspects and services dropper posts on all pre-owned and Certified Pre-Owned bikes.
If you have any questions or concerns about finding your next gravel or cyclocross bike, our Ride Guides are available seven days a week to answer questions and help guide you in your search for the perfect bike.