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How Choose a Gravel Bike

By Jeremy Benson ⋅ Senior Review Editor
Thursday November 7, 2019
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What is Gravel Biking?


Gravel biking has exploded in popularity in recent years and is currently one of if not the fastest-growing market in the cycling industry. For the most part, the name gives it away; gravel biking is essentially riding a bike on gravel or dirt roads. You can think of it kind of like road biking but on dirt roads instead of pavement and usually with somewhat knobby tires. In the United States, there are many many thousands of miles of dirt roads scattered from coast to coast, from the plains to the mountains, making gravel riding accessible to most people in most locations. It is appealing to many because it gets riders out on less-traveled roads in what is typically a more peaceful environment where you can enjoy nature and scenery with less distraction from vehicular traffic, etc. The beauty of gravel bikes is that they aren't limited to just dirt roads, as you can ride pavement and mellower trails on them as well.

As the sport has grown in popularity, so to have gravel events with races like the Dirty Kanza, Lost and Found Gravel Grinder, Grinduro, and many more attracting thousands of competitors and participants to race competitively, push personal limits, or just have a good time with friends while exploring new places. Others use gravel bikes for bike touring, bike packing, or adventure riding. With gravel bikes and riding, you can choose your own adventure, whether that's chasing podiums or simply being out there, it's all up to you.

Gravel riding has taken the cycling world by storm. This popular style of riding is just what it sounds like  riding your bike on gravel roads.
Gravel riding has taken the cycling world by storm. This popular style of riding is just what it sounds like, riding your bike on gravel roads.

Do You Need a Gravel Bike?


When people first started to get serious about gravel biking, there weren't really any gravel-specific bikes on the market. People modified road and mountain bikes or just used cyclocross bikes to get themselves out there. As the gravel market continues to expand, manufacturers have taken notice, and now virtually all of the major manufacturers have gravel-specific bikes in their line ups. Some smaller manufacturers have even sprung up, focusing exclusively on the gravel market, and recently Shimano has even released its GRX line of gravel-specific components.

The truth is, you don't need a gravel bike to go gravel riding. Any bike that you can comfortably and safely ride on dirt roads will suffice. Whether that's your old hardtail or the cyclocross bike you haven't raced in years, it'll probably work to get you out and enjoying some dirt road riding. Manufacturers have honed in on what makes a good gravel bike, however, with geometry, tire clearance, frame compliance, and gravel-specific components like flared handlebars and compliant seat posts that can potentially make your gravel experience more comfortable and efficient. One nice thing about most gravel bikes is that they are highly versatile and can easily double as a road bike and tackle some light duty singletrack riding as well.

Gravel Bike Considerations


Just like any other type of bike, there's a lot to consider when deciding what gravel bike to buy. They come in all shapes and sizes, frame materials, wheel sizes, and builds to suit varying needs and budgets. It is important to consider where and how you ultimately plan to ride your gravel bike, as well as how much you're willing and able to spend.

Frame Material


Gravel bike frames are produced in every material you can think of, although the most common are aluminum and carbon fiber. Many of the larger bike brands produce their frames in both materials to offer their bikes at different price points to suit a wider range of tastes and budgets. Some smaller manufacturers produce frames in steel and titanium as well, though those materials are typically a bit more niche.

The Ibis Hakka MX has a very lightweight and stiff carbon frame.
The Ibis Hakka MX has a very lightweight and stiff carbon frame.

Carbon vs. Aluminum


The majority of gravel bike frames are produced in either carbon fiber or aluminum. Both materials work very well for creating bike frames, but they do have some distinct differences. Aluminum is a relatively lightweight material that is inexpensive to produce and fabricate. Aluminum frames are almost always less expensive than a carbon fiber frame, though they are typically a bit heavier as well. Aluminum frames had been known for being stiff and harsh, although modern production methods have helped to create more compliant and comfortable ride qualities. Carbon fiber is a very lightweight material with a high strength to weight ratio. Carbon fiber is significantly more expensive, as is the cost of the molds with a more involved production process making carbon frames and components more costly to the consumer. Not only is it lightweight and stiff, but carbon fiber can be manipulated in the production process with varying layups to produce distinctly different ride qualities, but you will pay a premium price for the "fancier" material.

Frame Size


Gravel bikes are most commonly sized in centimeters, similar to road bikes. For example, our six-foot-tall testers were riding 58cm frames which would generally equate to a size Large. Most manufacturers offer their frames in multiple sizes, usually at least five, to suit a large range of heights. If you are unsure of the size you need, manufacturer's websites typically have a sizing guide chart to assist you.

Swapping between wheel and tire sizes during testing.
Swapping between wheel and tire sizes during testing.

Wheel Size


Gravel bikes generally come with either 700c or 650b wheels. Larger wheels are more common, and 700c is the same size that you'll find on most road bikes. 27.5-inch or 650b wheels are popular with some riders and are typically used to run wider tires for added cushion and traction. Many frames are designed to work with either wheel size, and some manufacturers give you the option to choose the size you prefer when purchasing a complete bike. It comes down to personal preference, 700c wheels typically provide greater rolling speed, while those interested in a more comfortable ride or a more mountain bike-like performance may enjoy the benefits of 650b wheels and larger tires.

Gravel tires come in a huge range of styles and designs. The Maxxis Ravager is a good example of a gravel tire with relatively low-profile center tread and taller more pronounced side knobs.
Gravel tires come in a huge range of styles and designs. The Maxxis Ravager is a good example of a gravel tire with relatively low-profile center tread and taller more pronounced side knobs.

Tires


One of the defining characteristics of a gravel bike is the tires. Unlike a road bike where you want a smooth and narrow tire to reduce rolling resistance on paved surfaces, gravel riders usually opt for tires with more girth and air volume, as well as some tread that adds traction on variable surfaces. The gravel bike tire market has grown as quickly as the market has expanded, and there are many tires available in a huge range of sizes and tread patterns to suit varying conditions, terrain, and preferences. Riders who frequent smoother gravel road surfaces may be happy with a faster rolling low-profile tread while those who ride rougher roads or singletrack may opt for more aggressive tread patterns for more cornering or climbing traction. Just like the wheels they mount on, gravel tires are available in either 700c or 650b sizes. The width of the tire you choose will depend on where and how you ride as well as the tire clearance of your bike's frame. Manufacturers have been steadily increasing the tire clearance on gravel frames with most bikes now being able to fit up to a 700c x 45mm tire or 650b x 2.1", and some can go even wider. Wider tires have greater air volume, can be run at lower pressures to increase the contact patch and traction, and also provide some additional cushion for a slightly smoother and more comfortable ride. Most serious gravel cyclists prefer tubeless tires so they can run lower tire pressures for more traction as well as a reduced likelihood of pinch flats.

Build


Gravel bikes come at a range of prices that are typically dictated by the frame material as well as the build or component specification. Entry-level aluminum-framed models with budget-conscious build kits can be purchased for around $1,000, while top of the line carbon bikes with carbon wheels and electronic shifting can cost up to $10,000. Most manufacturers make their gravel bike models in several build kits at varying price points. An example of this is Santa Cruz Bicycles who offers their Stigmata in a carbon frame only in five build options ranging from $3,599 up to $9,899. How much you're willing to spend is ultimately up to you and your goals as a gravel cyclist. The differences in componentry may not matter to many riders but may be very important to those with competitive aspirations. Many frames can also be purchased as a frame and fork only, allowing the rider to choose the components themself to create their dream build.

An example of a wide range 1x11-speed drivetrain. SRAM Rival is a common mid-range spec on complete builds.
An example of a wide range 1x11-speed drivetrain. SRAM Rival is a common mid-range spec on complete builds.

Drivetrain


Most gravel bikes come with either a 1x or 2x drivetrain, numbers that refer to the number of front chainrings. The trend of simplifying the drivetrain by removing the front shifter and derailleur has taken over in the mountain bike world and is also preferred by many gravel cyclists. 1x drivetrains usually have 11 or 12 gears on the cassette and provide a wide gearing range with narrow-wide chainrings and clutched derailleurs that help reduce the likelihood of a dropped chain. The lack of a front derailleur also helps to reduce drivetrain noise over rough terrain. The 2x drivetrain setups are still relatively popular among some cyclists as they have even more gear range, similar to that found on most road bikes. Riders who ride their gravel bike on the road regularly or those who live in areas with flatter terrain may enjoy having more top end gears for laying down the power. Crankarm length is another consideration as riders of different heights have varying needs, and gravel bikes have relatively low bottom brackets. Some manufacturers offer their bikes with different length crankarms depending on frame size, with smaller frames getting shorter lengths and larger frames with longer lengths for riders with longer legs. Many manufacturers spec road bike components on their gravel models while others are putting mountain bike or gravel specifics parts on theirs. Like anything in the cycling world, there are lots of options.

Brakes


The majority of gravel bikes come equipped with disc brakes, either hydraulic or mechanical. Mechanical disc brakes are actuated by a cable and are generally found on lower-end builds. Hydraulic disc brakes are usually more expensive than their mechanical counterparts as they are slightly more complicated with hydraulic fluid actuating the pistons in the brake calipers. Like any bike part, hydraulic disc brakes come in a range of performance levels and prices. Either type of disc brake usually works pretty well as they are typically less affected by moisture and mud than rim brakes. Rim brakes are still in use among some gravel riders, although they generally are only found on custom builds.

Many gravel bikes come spec'd with wider flared handlebars for increased comfort and improved handling.
Many gravel bikes come spec'd with wider flared handlebars for increased comfort and improved handling.

Cockpit


Cockpit setups on gravel bikes have been evolving with some gravel-specific products like handlebars and seat posts made to enhance comfort and performance for dirt road riding. Most gravel bikes come with drop-style handlebars like those found on a road bike while some gravel bikes can be purchased with a flat bar like you would find on a mountain bike. The flat bar is preferred by some riders to improve balance, stability, and handling, or to achieve a more mountain bike-like feel. Drop handlebars come in all shapes and sizes and vary in width and construction and "flare". Many bars come in a range of widths to suit riders' preferences with wider handlebars typically providing a higher degree of front end stability and steering leverage. "Flare" refers to the drops of a drop handlebar being bent, or flared, out to the sides at varying degrees. Flare is measured in degrees from 0 up to about 25-degrees with the most common flared bars falling about midway between those numbers. A flared bar makes the width of the drops wider than the hoods, which helps to increase stability and control through a wider and more balanced upper body stance in the drops. The shape of a handlebar's tubing also varies to make a bar more comfortable for extended periods with features like flat tops. Some manufacturers have even gone so far as to engineer their bars to be compliant, helping to take the edge off vibration and impact to reduce hand fatigue. Handlebar tape is another thing to consider, as it comes in a wide array of thicknesses and padding levels, which can also play a role in comfort and performance. Just like handlebars, some seat posts have also been designed to be compliant and flex towards the back of the bike to provide some relief from road chatter and vibration. Some riders will even put shorter travel dropper seat posts on their gravel bikes to lower their saddle for extended descents.

Suspension is still a rarity on gravel bikes  although the Future Shock found on Specialized Diverge models is a unique approach that provides 20mm of travel.
Suspension is still a rarity on gravel bikes, although the Future Shock found on Specialized Diverge models is a unique approach that provides 20mm of travel.

Suspension


The vast majority of gravel bikes are fully rigid, meaning that they have no suspension in either the front or rear of the frame. There are a few exceptions to this rule, with some manufacturers coming up with innovative ways to take the edge off of impact and the high-frequency vibrations associated with riding on rough surfaces. An example of this is the Future Shock design used by Specialized on their Diverge models. This unique suspension design is housed in the head tube and allows for 20mm of suspension in the handlebar. A few brands like Cannondale and Niner have gone so far as to make gravel bikes with some rear suspension, although this isn't especially common. Other manufacturers are getting creative with compliant handlebars and seatposts designed to flex and provide a small degree of vibration dampening, though this can hardly be considered suspension. Many riders modify their gravel bikes by adding suspension forks like a Fox 32 Step-Cast, but this is generally an aftermarket purchase that isn't offered on most complete gravel builds.

Some bikes come prepared to mount accessories  racks  and bags for bike packing or touring.
Some bikes come prepared to mount accessories, racks, and bags for bike packing or touring.

Versatility


Gravel bikes are highly versatile and typically not limited to any one style of riding. They can easily be used for commuting, road riding, bike packing, touring, and even mellower singletrack rides. How you choose to use your gravel bike is ultimately up to you, although some bikes are more oriented towards adventurous riding like bike packing or bike touring. These will often have a more conservative or upright geometry and may also come with many threaded accessory and rack mounts. Salsa and Niner are a couple of brands notorious for their wealth of mounting options. Other bikes are somewhat more race-oriented, with super stiff frames and lightweight builds that prioritize speed and efficiency over comfort.

Gravel bikes are a great way to get out and explore. Whether you're racing or just riding for fun and fitness  there's a bike to suit your needs and budget.
Gravel bikes are a great way to get out and explore. Whether you're racing or just riding for fun and fitness, there's a bike to suit your needs and budget.

Conclusion


We hope the information presented here helps you understand and navigate the often confusing process of making a new bike purchase decision. There are lots of gravel bikes to choose from, and the market continues to expand as this genre of cycling continues to grow in popularity. The most important thing is to understand your goals as a gravel rider and to get a bike that best meets your needs and budget, then get out and ride.


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