Yes, A Gravel Bike Can Be Fast

We took one look at gravel riding and decided that gravel bikes could be designed for rough roads and for speed. This invites the inevitable question: what’s the difference between a gravel bike designed this way and a road bike? Here’s one perspective.

Gear aside, if you’re here and new to gravel get a feel for the spirit of this discipline from some of our ambassadors. If you already know the score, hit the next section.

Gravel bikes vs road bikes, what’s the difference?

 

A gravel bike is the do-it-all companion where a road bike just won’t cut it. Although it’s fair to say that road bikes can be organized into a number of different categories, for our purposes we’ll say we’re not going to include triathlon, time trial, or track bikes here. We’re focused on bikes like the S5, R5, or Caledonia compared to our gravel bike, the Áspero.

With a focus on engineering fundamentals like aerodynamics, weight, and stiffness, road bikes are designed to find all the slivers of speed on asphalt descents and long-technical climbs. Riding down a paved mountain pass, nothing responds like the R5. Lean hard into a dusty corner on a fire road and you’re less likely to feel the same way. Meet the gravel bike—designed to go where a road bike would quickly find its limits.

While the profile of a road and a gravel bike look similar at first glance (which is also why you’re likely digging around for information), it’s the details like geometry, tire clearance and wheel size options, gearing, and components that set gravel bikes apart from their tarmac loving counterparts.

Riding the Aspero through the woods

Geometry 101: fit for the trails

 

This boils down to a couple of general points and a few specific design choices that include trail values, wheelbase length, bb drop, and how those work together to create the sensation of stability and smooth handling that inspires confidence when you’re going fast on rough, beat-up roads.

Trail values get longer to bring the handling in line with what feels more appropriate for rough roads. Trail is the front-wheel response to rider input, and it’s the most critical factor in high-velocity handling. On the Aspero this is adjustable with the TrailMixer, a flip-chip built into the fork.

Some gravel bikes also offer the option of adjusting to multiple wheel sizes: both wide 700c rims and tires and 650b wheels. This kind of versatility is what extends the limits of a gravel bike beyond that of road. More on that later.

Your wheelbase typically gets longer, which gives you more room to adjust weight fore and aft as needed, a critical part of riding fast or racing when you don’t know exactly what the road ahead holds. 

The frame geometry is typically more upright and designed to give you the body position to achieve the control and comfort—key for putting in miles in more technical terrain. Frame designs like the Aspero shift the design priorities towards power and aggressiveness but still less so than an aero race bike like the S5.

BB drop gets lower—which in turn positions your center of pedaling power lower and, in combination with the changes mentioned above, adds yet another layer to the confidence/stability/plantedness equation oh-so-critical for having a good time on gravel roads.

Wheel width and tire clearance: 28mm, 40mm, and 650b

 

Wider wheels and tires are finding their way onto road bikes but when it comes to all-out traction, the gravel bike once again finds its strength.

Where you might be able to sneak a 28-30mm tire into a race-ready road bike (this is not legal advice: check the specs), the gravel bike will gladly take on a 35-40mm tire or a 650b wheel and tire without compromising the ride or creating rub. Even better, that extra width means more rubber to find grip on dirt and more grip means more confidence at speed. 

The dedicated rider looking for a one-bike solution could easily run two wheelsets, one fitted with an aggressive tire for beat-up roads (or gravel racing) and one with a less aggressive profile for riding on the road. Tire selection is ever-increasing, too, so there are always new mixed surface options out there to make your gravel bike even more capable no matter what your local riding offers.

So what about 650b? What’s the difference between a 700c wheel with a wide tire and 650b? A 650b wheel is smaller in diameter. This allows you to run a high-volume, wider tire on the same frame as a 700c setup. Additional tire volume means you can run lower tire pressure—a significant benefit for riding on particularly technical trails, on the softest, sandiest dirt or fresh loam.

1x chain and front chainring on a gold Aspero

Components and Gearing: The Power of Disc Brakes and the Choice Between 1x and 2x Drivetrains

 

Disc brakes are here to stay, and for gravel bikes they’re essential. Less than inspiring riding conditions in dust, rain, mud, and more warrant the kind of stopping power and reliable control that disc brakes can offer.  

Now, the eternal debate over gearing: 1x vs 2x chainrings/drivetrains. 

1x configurations will likely use a 11-42 or 11-40 cassette paired with a 40 or 42-tooth chainring. With fewer moving parts and materials, these setups are easier to maintain, lower in weight, cleaner in design and configuration, and continue to evolve as drivetrain manufacturers fit more powerful and efficient gearing into tighter packages.

On 2x setups, 48 and 31 tooth chainrings with an 11-34 cassette are the most common. This setup provides you more gear range and closer gear ratios, which can be a big advantage when your ride goes up, up, and more up.

Use cases and preferences obviously vary, so it’s best to examine your perspective on simplicity over the complexity of maintenance and your particular needs for where and how you ride. What’s advantageous for grinding out big-mile days in the desert may not be as ideal for competition or your next FKT attempt.

The CNCPT team riding Asperos on desert sand

Going the distance, going for speed

 

Riding with your friends is one way to find freedom and feed your hunger for turning some pedals, racing is another. Like road, the race scene is all its own, and it’s become one of the most accessible and enjoyable forms of bike racing out there these days.

 

Elite racing

Gravel racing has a different flavor than its road equivalent. in gravel; the elite races have grown and are growing more from local gravel grinders into elite level competitions. You’d have to stack up a lot of UCI points and hard-earned credentials to compete with the pros on the road, but on gravel, you’re given the opportunity to rub shoulders with anyone: from podium contenders to passionate enthusiasts. Everyone’s playing on the same field so to speak, and that’s the beauty. You get the highest caliber course, support, and competition with fewer barriers to entry. 

A quick search online for ‘gravel races near me’ or the equivalent will yield lists and lists of races in your immediate area or at least your country. Some of these races have entry caps to limit the field size (which offers a better overall experience for competitors), and once you’re ready, races like this are worth researching, training, and planning for and they’re a great way to test your mettle. 

 

Fastest known time racing

Fastest known time (FKT) is an entirely unique bit of competition. All that’s required is a clear idea of the “course”, some gear to track your time (a computer), and a game plan. Although the details can get a bit more complicated (supported vs. unsupported is an example) The format is simple—pick a ride, note the fastest recorded time, and try to beat it within the same constraints as the rider at the top. 

Some of the highest-profile records are set by elite riders, but this style of competition really is anyone’s game. Even better about FKTs on gravel? You don’t have much to contend with in regards to traffic or other riders (be respectful wherever you ride)—it’s you against an agreed-upon route and the clock. 

Information about agreed-upon FKT routes and records is more dispersed, closely-held (personally), and more difficult to research but not impossible to find. One easy way to get going is to start with local routes and work your way up—race with your friends and then start asking your way out from your local bike shop as your set your sights higher and higher.

 

Explore more of Cervélo Gravel

 

Aspero-5

Aspero-5

  • Colors: Lime Shimmer Five Black Purple Sunset
  • Options: 4 models / Disc only
  • Priced: From CA$8,850.00
Áspero

Áspero

  • Colors: Black/Gold Seabreeze Red/Carbon Grey/Seabreeze
  • Options: 7 models / Disc only
  • Priced: From CA$3,700.00