Gravel riding has become increasingly popular among avid road cyclists like us, who love the versatility and adventure they bring to our cycling routines. But our road bikes don’t take to the gravel as well as we do. Off-roading brings a variety of terrain with technical challenges that a road bike isn’t equipped to face. Gravel bikes, on the other hand, are designed to take us anywhere off the beaten path we want to go. At first glance, a gravel bike could be mistaken for a road bike, but subtle differences give it an advantage on rough and muddy trails. We’ll explore the nuances of gravel bikes versus road bikes so you can decide if investing in a gravel bike makes sense or if it’s best to rig your road bike to travel over gravel.
What is a gravel bike?
A gravel bike is designed for stability, comfort, and agility on distance rides over gravel trails or any other type of unpaved terrain. The gravel bike blends qualities of road, cyclocross, and mountain bikes along with other unique features that enable it to navigate rough roads with ease. Gravel bikes come in different styles– “aero gravel bikes” are designed for speed and performance, while others are made for comfort on longer adventures. But all gravel bikes prioritize stability and handling over rough or weather-beaten paths.
A gravel bike’s frame is structured with enough clearance for wide tires with low pressure and tread to grip gravel, sand, or mud and supports an upright, comfortable riding position on bumpy trails. Gravel bikes are the happy medium between stability and performance–even though they’re built to handle hard knocks on rough rides, they’re still lightweight (usually only a few pounds heavier than a road bike).
A gravel bike has drop bars, disc brakes, and a slim frame like a road bike, but its structure is less aerodynamic and sturdier. Cyclocross and gravel bikes have many features in common, but cyclocross bikes have a shorter wheelbase for a more aggressive position during races lasting an hour or less. Cyclocross bikes aren’t made for long gravel adventures and have no mounts to store bottles or luggage. Mountain bikes have wide, treaded tires like gravel bikes, but gravel bikes have more aggressive gearing and perform better on paved roads.
What is a road bike?
Road bikes are designed with a lightweight frame and slick, slender tires for riding at high speeds on paved roads. Road bikes fit into one of two categories–racing bikes or endurance bikes. A racing bike’s geometry is constructed for maximum aerodynamic potential, whereas an endurance bike is made for relaxed, long-distance riding. A road bike can be ridden off the road but is limited to light gravel in dry weather conditions. The aerodynamic design of a road bike is vital for road racing, but it makes the bike less stable in rough riding conditions when compared to a gravel bike.
What are the differences between gravel and road bikes?
A gravel bike may look like the spitting image of a road bike, but with a closer look their unique qualities start to stand out. The differences between gravel and road bikes aren’t obvious, but they are significant. You’d never dare join a road race with a gravel bike or take your road racing bike out for miles on a wet and muddy trail. If you inspect the two bikes side-by-side, here are the differences you’d find and why they matter.
1. Frame structure and size
A gravel bike frame is reinforced for stability and durability while maneuvering through rocky, muddy, or sandy paths. Its frame is 2–7 pounds heavier than a road bike, which means it’s sturdier but still quick. You’ll find carbon fiber road and gravel bike frames, but gravel bikes are more commonly made from aluminum or steel for extra strength to combat debris and support accessories like mudguards or cargo racks.
A bike frame determines a rider’s position. Road bike frames support an aggressive riding position with a shorter wheelbase and stack height and a larger head tube angle (71–74°). Gravel bike frames support an upright and relaxed position with a longer wheelbase, taller stack height, and slacker head angle (68–71°). A wheelbase is the distance between both axles, and the stack height is the distance from the center of the bottom bracket and the top of the head tube. The head tube angle forms at the intersection of the wheelbase and the stack height.
The road bike’s shorter wheelbase gives more responsive handling and swift acceleration. The slacker head angle on a gravel bike positions the cyclist further back and in a more upright position and moves the front wheel forward and the handlebars closer to the cyclist. This slows the handling and makes it easier to navigate technically challenging terrain at slower speeds, and eliminates the shakiness you’d feel with the more responsive handling of a road bike.
2. Wheels and tires
The wheels and tires of gravel bikes and road bikes are the most noticeably different features. They each work best with different types of tires in different sizes.
Tubeless tires are best for gravel bikes, but tubed tires are more common on road bikes. Gravel bikes use tubeless tires for puncture prevention since these tires are filled with sealant instead of a tube that seals small cuts made on rugged terrain. Tubed tires on road bikes are more prone to pinch flat, but they’re easier to service. Gravel riding also requires lower tire pressure (30–50 psi) for better grip and traction, and tubeless tires are capable of operating at lower pressures.
Tire clearance and size
A bike’s tire clearance determines the widths of its tires. Gravel bikes require extra clearance to make room for the mud that can build up on the tires and also larger tires for more contact and greater grip on the ground. Road bikes, on the other hand, don’t have any mud to worry about, so extra clearance isn’t necessary.
A road bike has a maximum tire clearance of 30mm, but most fall between 24–28mm and are fitted with 700c wheels. Gravel tires can range in size anywhere from 28mm–47mm, but 40mm is average. Gravel bikes have a wider selection of tires than road bikes because they encounter a wider variety of terrain. Gravel tires can be paired with 700c wheels or slightly smaller 650b wheels. Smaller wheels provide more clearance for larger tires. A gravel bike may also have a dropped drive-side chainstay that curves to accommodate a larger tire.
700c wheels with slightly wider tires are often preferred over 650b wheels with fat tires for road cyclists who enjoy the occasional gravel ride because it allows us to transition between gravel and road without feeling like we’re at a disadvantage.
Tire tread pattern
Unlike most gravel bikes, road racing tires need to be slick because resistance is a hindrance to speed. Road tires need minimal resistance to maximize speed and require narrower, lighter tires. Gravel tires need more tread to grip wet and uneven surfaces, but just how much more tread they need depends on the terrain they frequently encounter. Cyclists who transition from road to gravel in a gravel race and still need to maintain speed would choose a more aerodynamic gravel bike with slicker tread. But cyclists who ride for adventure would choose a more aggressive tread pattern. Weather conditions also influence the type of tread you choose for a gravel bike–a wet trail requires more tread than a dry one.
3. Gears and chainrings
Road bikes use a 2x drive train, meaning they have two chainrings in their crankset. Gravel bikes can have either a 1x or 2x drive train. Both types of drive trains have the same gear range, but 1x uses fewer gear shifts within that range. This means that there’s a more significant difference between gears. A 1x drive train has 11–12 gears, while a 2x has 22–24. With a single drive train, a front derailleur that pushes the chain from one chain ring to the other to change gears isn’t necessary, and gear changes are simpler because only the rear chain needs to shift gears.
There are pros and cons to 1x and 2x drive trains, and the best choice depends on your goals and preferences. Without the front derailleur, a 1x drive train saves weight. It also decreases your bike’s chances of dropping chains (when the chain falls off the front chain ring) on rough rides. However, a change in gears is much more noticeable with a 1x drive train. It limits your gearing options, which can be a problem on steep ascents and is not preferable if you want to achieve specific cadences. 2x drive trains are used on road bikes because they offer greater precision with gear shifts. Also, the front derailleur provides more and smaller gear shifts, which helps you maintain a steady cadence.
4. Bike features
Both road and gravel bikes have handlebars with drops, but gravel handlebars often flare out for a wider grip and greater stability. Road bike handlebars don’t flare to maintain a narrow, aero profile.
Unlike a road bike, a gravel bike may also have a dropper post that allows you to drop your saddle as you ride, not so you can fine-tune your seat height but so that you can get behind your saddle on steep downhill stretches and not tumble over the top of your handlebars.
Road bikes use three-bolt SPD-SL style pedals made of plastic to cut weight. Gravel bikes usually use SPD pedals, like mountain bikes. SPD pedals are made of metal, which makes them more durable. They include recessed cleats that make it more comfortable for walking your bike than SPD-SL, and they’re double-sided so that you can clip into either side of the pedal.
Gravel bikes also have mounts so you can attach accessories like mudguards, racks, and extra water bottles for multi-day adventures. Road bikes usually don’t have an option for extra accessories since you can fit whatever you need for a road ride in the pockets of your cycling jersey.
Can you use a road bike as a gravel bike?
A road bike can be ridden on light dirt or gravel without a problem, so if that’s as rough as your off-roading gets, then stick with your road bike. Endurance bikes are best for riding on light gravel since they put you in a more stable riding position and have more tread on their tires than road racing bikes. But a road bike does not have enough stability nor wide enough tires for rugged rails and could get damaged. A gravel bike is much better suited for off-roading.
Can you put gravel tires on your road bike?
You can put wider tires on your road bike but only up to a certain size. Racing bikes usually only have enough clearance for 28mm tires. You can fit up to 35mm tires on an endurance bike and up to 40mm on a cyclocross bike, so those are a better choice for gravel rides than your road racing bike if you have them. If your tires are too wide for your road bike, they’ll rub the frame and leave no clearance for the dirt that sticks to tires on gravel rides. Rough gravel usually requires at least 32mm tires. If your bike can’t fit wide enough tires to meet the demands of the terrain, then it’s best to use a gravel bike. And if you’re seeking really steep and rugged terrain on a regular basis, a mountain bike may be best for you.
Can you use a gravel bike as a road bike?
A gravel bike can be ridden on the road, and if it leans more toward the aero end of the spectrum, you’ll find that it performs fairly well. But in a road race, your gravel bike won’t stand a chance against experienced cyclists on road bikes, especially if it has a 1x rather than a 2x drive train. But a gravel bike can make a great winter road bike with excellent traction for the off-season.
If you have to make a choice between a road or gravel bike and 1) aren’t a pro road cyclist, 2) aren’t planning to compete in road races, and 3) frequently ride on roads and gravel, then a gravel bike is probably your best choice. It’s easier to ride on the road with a gravel bike than it is to ride on rough gravel with a road bike. Many cyclists with gravel bikes will switch out their gravel tires for road tires with less resistance.
Road cycling is in our blood, but we’re also big fans of gravel riding. Our 2024 Gran Fondo Hincapie calendar will see a new addition–a gravel fondo through the foothills and mountains of California’s Central valley. Register for the Merced Gran Fondo Hincapie for a fun gravel adventure. Or join one (or more) of the 20 best gran fondos in the USA.
We’re all about adding variety to our cycling training. If you’re looking for a new bike trail, here are a few of our favorites.
- 11 Best Bike Trails in South Carolina
- 10 Best Bike Trails in North Carolina
- 10 Best Bike Trails in Georgia
If you’re shopping for a new bike, check out our guide on how to buy a road bike and learn how to measure sit-bone width to find your saddle size or how to find the right road bike size.