If you could only have one type of bike, which should it be? A road bike or a gravel bike? Both bikes have their pros and cons, and the answer to this question really depends on what you plan to use your bike for. In this blog post, we will discuss the differences between road bikes and gravel bikes, so that you can make an informed decision about which type of bike is right for you!
For the sake of comparison, when we talk about road bikes in this article, we’re referring to performance-oriented road bikes and not endurance bikes. Also when we talk about gravel bikes, we’re referring to adventure off-road bikes and not cyclocross bikes.
In a Nutshell: Road Bike vs Gravel Bike
Road bikes are designed for riding on paved surfaces. They are lightweight and feel agile thanks to their geometry and slim tires. Gravel bikes are designed for riding on unpaved surfaces. The geometry leans towards stability and upright body position, and the wide tires can absorb rough road vibrations better.
Most road bikes today can be used for gravel too, thanks to disc brakes and a wider maximum tire width. All you need to bring a road bike off-road are wider tires, probably tubeless. The geometry won’t be ideal, but it’s not a deal-breaker for most people. On the other hand, you can make a gravel bike faster on paved roads with slick and slim road tires.
Road bikes have some clear advantages over gravel bikes:
- Road bike frames are more aero and high-end road bikes come with deep-section rims that are more aero
- Road bikes are comparably faster on paved roads thanks to their lower weight and better aero, this is important if you are racing
And gravel bikes also have some advantages over road bikes:
- Gravel bike frames have wider tire clearances and can handle rougher roads more comfortably
- Gravel bike frames have more mounting points which are important for bags and mudguards
- Some gravel bikes have bigger maximum weight limit than road bikes
Next, let’s see in more detail what are the difference between typical road bikes and gravel bikes.
Frame Geometry
At a first glance, road bikes and gravel bikes might not look that different. After all, they both have diamond-shaped frames and usually come with a drop bar and 700c wheels. However, upon closer inspection, there are some key differences in frame geometry.
Road bike frames have a steeper headtube angle and a lower stack. This results in a more aggressive riding position which is ideal for going at speed. Road bikes also have a shorter wheelbase, making them more agile.
Gravel bike frames have a slacker headtube angle and a higher stack. This puts the rider in a more upright position, which is better for long-distance riding and comfort. Because of the higher stack, gravel bikes tend to have a sloping top tube.
Gravel bike frames also have a longer wheelbase, which makes them more stable. This also allows them to have bigger tires and avoid toe overlap with the front wheel which is important for handling on rough and technical roads.
Road bikes’ bottom bracket is lower than gravel bikes. This lowers the riders’ center of gravity and gives them better confidence during fast cornering and descending. Gravel bikes’ higher bottom bracket will give the pedal more ground clearance which is important when riding on uneven ground to avoid pedal strikes.
Tire Choice and Tire Clearance
For most people, this is the main deciding factor between a road bike and a gravel bike.
Road bikes today come in stock with tires that are 25-28mm wide. In the past, road bikes used to have much narrower tires (23mm), but the trend in recent years has been to go wider for comfort. And so, most newer generation road bikes can fit up to 34mm wide tires (even if they don’t officially say so), which are usually good enough for unpaved and smooth dirt road riding.
Gravel bikes come with even wider tires, they come in stock with 40mm tires and can sometimes go up to 50mm. They have higher rolling resistance but they offer much more comfort and grip.
If you ride mostly off-road, you will definitely need a gravel bike instead of a road bike. On the other hand, if you do most of your riding on paved roads and want to occasionally venture onto unpaved roads, dirt, and loose gravel, you can get away with a road bike.
If you’re not sure what kind of riding you will mostly be doing, it’s probably best to lean more on the side of getting a road bike. This is because road bikes today are getting more versatile and can be used in a broader variety of terrain. Also, beginners are more likely to ride on paved roads or dirt than a highly technical off-road terrain.
Road vs Gravel Groupset
A groupset is a collection of parts that make up the drivetrain of a bike. It includes shifters, derailleurs, a crankset, a chain, and a cassette.
Road bikes usually come with 2x drivetrains while gravel bikes come with 1x or 2x drivetrains. A 2x drivetrain has two chainrings in the front and offers a tighter range of cassette gears. This is ideal for road riding because it allows you to spin at a preferred cadence on a fast flat road and still have low gears for climbing hills.
A 1x drivetrain only has one chainring in the front and fewer gears overall. It is simpler because it removes the need for a front derailleur, but you will have fewer gears to work with. This doesn’t matter as much as a road bike because on a gravel bike you’re going to be riding at slower speeds.
Some gravel bikes come with 2x drivetrains for riders who want the option to ride on both paved and unpaved roads.
Thankfully, road and gravel groupset components from the same brand are fully compatible. So, if you have a road bike with a road groupset and you want to turn it into a gravel bike, you can easily do so by swapping out the rear derailleur and cassette with ones that are more suited for gravel. Gravel rear derailleurs usually have a clutch mechanism to prevent chain slap.
If you’re not sure which groupset to get, Shimano 105 and Ultegra are two of the most versatile groupsets. They are road groupset but the 105 in particular is compatible with up to 36t cassette, which is big enough for any gravel riding. The maximum of 34t on Ultegra is also good enough most of the time. Shimano road groupset is perfectly capable when used off-road.
Shimano’s gravel-specific groupset, the GRX, is good if you need more reliability on the roughest road condition. The most noticeable difference, really, is in the hood design and cassette capacity.
Suspension
Both road and gravel bikes don’t come with full suspension. But, some gravel bikes have suspension forks or some kind of vibration dampeners. For example, the IsoSpeed decoupler in Trek Checkpoint and Future Shock in Specialized Diverge.
A suspension fork will make your ride more comfortable on rough roads but it comes with a few drawbacks. First, it is heavier and will make your bike less efficient on paved roads. Second, it can be harder to control on descents because the front end of the bike is more prone to wobbling.
Generally, for riding on dirt roads or loose gravel, you don’t need any vibration dampeners because increasing the width of your tires will have the same effect.
Frame Strength and Materials
Road and gravel bike frames are available in aluminum, steel, titanium, and carbon fiber materials. The cheapest material is usually aluminum. Steel and titanium frames are good for longevity. But, for the performance-to-weight ratio, none can beat carbon fiber yet.
Gravel bike frames are tougher than road bike frames, but it doesn’t mean that road bike frames can’t be ridden off-road. They are both subject to the same ISO 4210-6 strength requirements under the same “racing bike” category. So, both road and gravel bike frames have the same capabilities, but gravel frames are stronger because they have thicker walls to dampen vibrations and a higher maximum weight capacity.
Handlebar Design
Gravel bikes have flared dropbars, which means the drop section of the handlebar is angled outward, making it wider than the hood. The flare supposedly gives you more control when riding on technical roads. In reality, most people don’t think flared dropbars have a significant advantage over unflared road dropbars in terms of control.
One clear advantage of flared dropbars is that it gives you more room to mount a wider handlebar bag.
Some road bikes have flat tops handlebars that are designed to be more aero than standard rounded tops. This can save up to 7 watts at a high speed. Gravel bikes don’t need flat tops because you don’t ride fast enough on gravel where the aero shape will give an advantage.
Gravel vs Road Bike Rims
700C is the most popular rim size for both gravel and road bikes. Though, some gravel bikes use the smaller 650B so they can fit bigger tires. Road bikes almost exclusively use 700C.
Gravel-specific rims are wider than road bike rims. The extra width allows better compatibility with wider tires, but on the downside, they can’t be used with slim road tires.
Just like the frame, road bike rims are usually strong enough for dirt and loose gravel road. Though, make sure you don’t fit wide tires on narrow rims.
As a general rule of thumb, double the internal width of your rim to get its approximate maximum tire width. For example, a 19mm rim can be fitted up to a 38mm tire, and a 21mm rim can be fitted up to a 42mm tire. (This is not always the same for all brands.)
Unlike road bikes, gravel bikes don’t usually use deep profile rims because you don’t ride fast enough on gravel to take advantage of the aero. A gravel bike’s rim depth is usually no more than 45mm, whereas road bikes can go up to 80mm.
If you plan on having only one bike for all roads, it’s much more convenient to have two sets of wheels: one for road and one for gravel. It’s easier to swap bike wheels than to remove the tires and install different ones every time, especially if you run tubeless.
If you really can’t afford a second wheelset, the best compromise is to get 21-23mm wheels and fit 30-34mm tubeless tires, depending on which side you lean more into. This setup is fast enough on paved roads and comfortable enough for gravel riding.
Mounting Points
This is another one of the clear advantages a gravel bike has over a road bike. At its heart, gravel bikes are built for adventures so they have more mounting points to allow you to attach all sorts of bike accessories, such as fenders, bags, and multiple water bottle cages. Some gravel bikes also have a built-in tool compartment on the downtube. Most road bikes only have two mounting points for bidons.
Gravel bike frames also have a higher maximum load that allows you to bring more gear with you on your adventures. Road bikes usually have a 130kg maximum weight limit including the rider because they are not meant to be loaded with gear.
That said, most bike bags don’t require mounting points and can be easily attached with velcro straps. So, you can still go on reasonable bikepacking trips even on a road bike.
Building a True All-Road Bike
As you can see, the line between gravel bikes and road bikes is blurry. And we purposely avoid endurance bikes and cyclocross bikes which makes the line even more blurry. Any of these four bikes can do almost everything, but none of them is the best at everything.
If you want to have only one bike for all types of terrain, you will still need to lean toward one or the other. Here’s what we recommend:
First, you might want to choose a road bike frame with a generous tire clearance (35mm+) and a relaxed geometry. Some examples are Trek Domane, Cervelo Caledonia, Enve Melee, and Allied Echo. If you lean towards gravel, it’s better to choose a simple gravel bike frame that is not bulky and doesn’t have off-road-specific features like fork suspension or dropper seat post. Some examples are Factor Ostro Gravel, Wilier Rave SLR, or Scott Addict Gravel.
Second, use a 2x drivetrain groupset with a big cassette. A 1x won’t be enough for riding on the tarmac and most of the time you won’t find the right gear for your preferred speed and cadence.
Third, get two sets of wheels—one for road riding with slim tires (25-30mm), and the other for gravel (34mm+). If you can only have one wheelset, choose a rim with 45mm depth or shallower, 21-23mm internal width, and 30-34mm tires. You can use this wheelset on both road and gravel.
Finally, don’t shave too much weight on your bike because this will usually reduce comfort. Lightweight saddle and handlebars can make your bike much lighter, but lightweight components will not absorb road vibrations well.
With this setup, you will have a bike that is light enough for road riding and fast enough for gravel riding. It won’t be the best at both, but it will be good enough. And it will be much cheaper than buying two bikes.
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