Are You Gravel-Curious? Here’s How to Choose a Bike.
As road frames evolve to become more capable on various surfaces, many roadies may find a sweet spot for their riding that’s short of a full-on gravel bike
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Last year my friend Dan’s Cervelo R5 was stolen out of his garage. Armed with a payout from his homeowner’s insurance, he started looking for a replacement, only to run headlong into the unprecedented product shortages caused by the pandemic-influenced bike boom.
Since simply replacing his R5 wasn’t possible on a short timeframe, he began to consider other options. Chief among them: whether to get a bike he could use for multi-surface adventures. Dan isn’t alone. Gravel is one of the fastest-growing segments in the bike industry. But traditional roadies like Dan don’t automatically gravitate toward it. They love how ultralight modern road bikes zip up climbs, along flats, and down descents. They love the zen of turning the pedals at 90 rotations per minute for hours on smooth asphalt. They’ve heard about gravel riding—these days, how could you not?—but they’re not itching to enter Unbound or go on a bikepacking trip. And they often live in areas where it takes a bit of pavement riding to reach the dirt. Call them gravel-curious.
That’s Dan. A longtime roadie, he was interested in expanding his riding horizons. But he lives in Denver and didn’t want to get stuck with a bike that was overbuilt for his needs and inefficient on pavement, with fat tires, slow-steering geometry, and unnecessary accessory mounts. Fortunately, there’s a newish breed of road bikes that seems ideal for riders like Dan.
What’s All This Alt-Road, All-Road Jargon?
The bike industry can never settle on one term. I’ve heard this niche called road plus, alt road, new road, and all-road. Whatever you call it, the subcategory is probably best defined by its attributes: clearance for somewhat wider tires than traditional road bikes (usually around 35 millimeters), classic road geometry, limited extra accessory mounts, and an emphasis on balanced performance for pavement and smooth dirt roads and trails.
Riders define all-road according to their own use and preference on necessary tire width, so it’s a wide niche. All-road encompasses road bikes from full-on race rigs that happen to fit 32-millimeter tires, like the Cervelo R5 or the Giant TCR Advanced Pro Disc, to models that are designed primarily for great ride quality and also fit 32-millimeter rubber, like Specialized’s Aethos. (Both of the latter two come stock with conventional 25- and 26-millimeter road tires, respectively.) This niche also includes changelings like Trek’s Domane, which debuted in 2012 as an endurance road bike and morphed into an all-road machine with clearance for 38-millimeter tires. And it covers purpose-built all-road bikes like Allied Bicycle Works’ Allroad. That’s all proof that all-road is as much about perception and marketing as it is about the physical specs of the bike.
“I think all-road is the ideal road bike for most people,” says Sam Pickman, Allied’s director of product and engineering. “Gravel really sparked people’s interest in exploring. But the fact is, most people live in cities where there’s not a ton of gravel riding available to them. The all-road bike is perfect because they don’t give up a lot of performance on the routes they normally ride, but they can jump off and do some dirt here or there.”
How We Got Here
It’s easy to see the influence of gravel on all-road bikes. But in many aspects, like geometry, all-road is essentially an evolution of the old endurance road category, says Pickman. The granddad of endurance road bikes is the Specialized Roubaix, which debuted in 2004 and was the first of a new genre that emphasized comfort, with features like a more upright rider position, vibration-absorbing technology in the frame and fork, and slightly wider tires.
Regarding wider tires: all tire-clearance figures here are as claimed by the bike maker, but they’re notoriously fuzzy. In reality, tire width varies based on the rim it’s installed on. Plus: ISO measurements require four millimeters of space between the tire and each chainstay or fork blade. As a result, many brands are conservative with clearance claims. Riders can and do fit wider rubber than a frame is rated to accept.
For a while, endurance road bikes struggled to find a role. Bike brands often marketed them as hardcore race bikes for cobbled classics like Paris-Roubaix, but then muddied the perception by adding elements like tall stack heights and low gearing that attracted a very different kind of rider. The result, as Pickman accurately points out, was that endurance road rigs always had a dorky rep as an old man’s bike. Then came gravel, which seemed to give these kinds of machines a specific design direction and purpose that endurance road lacked, as well as a fresher, younger-feeling expression.
Where Is It Going?
As with all new genres, all-road is evolving quickly as designers find innovative ways to make bikes more capable on various types of roads and trails. One notable example is Allied’s new model, the Echo, which uses flip chips: modular front and rear dropouts that let the rider adjust the geometry to a road or gravel setting. In the former position, you get a pretty classic road-bike geometry, with responsive handling and clearance for 30-millimeter tires. To switch to gravel mode, adjust the chips in the dropouts, which lengthens the wheelbase and boosts tire clearance to 40 millimeters; the steering relaxes a bit for more stability on rougher terrain.
Flip chips aren’t new; they’ve been around in mountain bikes for years. More recently, brands like Cervelo and Otso have begun using them for gravel rigs. But Allied is among the first brands to use them in both the front and the rear. It’s the most clever mechanism I’ve seen for expanding the range of a drop-bar bike.
The Echo, like all Allied bikes, is undoubtedly expensive. But the addition of flip chips makes it enticingly versatile. With two pairs of wheelsets (one shod with road tires and the other with gravel rubber), ten minutes, and a few Allen wrenches, you can get two different bikes in one package. Chips may be the way of the future for these bikes because, in addition to adjusting tire clearance, they offer geometry changes better suited for each style of riding than you’d get by swapping wheelsets alone.
What’s Right for You?
If your current road rig fits you, is mechanically sound, and you’re happy with it, then there’s no reason to change, no matter how old it is. But if it’s pushing ten years old and you’re thinking about a replacement (or, as in Dan’s situation, you’re starting from scratch), a new all-road model is going to be a noticeable improvement in versatility, not to mention components and ride quality.
An all-road bike is capable of even competitive road riding. Meanwhile, the disc brakes, broader gearing, and added tire clearance, which may range from four to ten millimeters more than a road bike, will open up a ton of terrain that would have pushed your old rig to—or past—its limits. And if you live in an area where your gravel options are limited or require a lot of pavement riding to reach, all-road is a great choice because it expands your options without major compromise for on-pavement efficiency. Even if you end up wanting a gravel bike, too, there’s not much downside here, since you’ll still have a kickass road bike that’s capable of mixed-surface adventures.
Surely there are drawbacks to the all-road approach, right? Or everyone would just be selling their gravel and road bikes, and refuting n plus one with an all-road setup. There are compromises, of course. Any time you’re looking to use one bike for multiple purposes, “you’re going to give up something,” no matter what style of bike you buy, warns Pickman.
From a performance road standpoint, all-road bikes usually lack a touch of the competition-focused edge you’ll find in a high-end race bike. There’s not much attention paid to aerodynamics, for instance. The longer wheelbases on all-road bikes can also create a less responsive feel, which matters in criteriums or on zesty descents that demand fast line adjustments. (This is why Echo-style flip chips are so neat: you really do get two geometries in one bike.) All-road stack heights are generally taller for better comfort on long rides, so it’s harder to get into a low, aerodynamic position.
Those factors might be meaningful if you really want to mix it up in races or competitive group rides. But even then, they’re subtle and probably won’t cost you a race. The more significant limitations are at the gravel end on the capability spectrum.
Most obvious is the tire clearance. When Open released its original UP gravel bike, which has clearance for 40-millimeter tires, it made a point of noting that you could run narrow road tires on the bike and still be pretty happy on a fast group ride. But if you get a bike that won’t accept more than 32- or 35-millimeter rubber, there’s nothing you can do if you want to go wider.
Second: while many gravel bikes feature more accessory mounts than most riders will reasonably use, most all-road bikes swing too far the other way. The Echo, for instance, has a third bottle mount on the underside of the down tube, but no fender eyelets or top-tube bag mounts either, which does hamper versatility a bit. Both limits—tire clearance and accessory mounts—are asymmetrical; you don’t have to use them if your bike has them, but you physically can’t on a bike that lacks those attributes. If you think gravel racing or bikepacking might be in your future, you might quickly outgrow an all-road bike.
The other reason an all-road bike might not be a good fit is if you have a newer road bike—especially one that has disc brakes and clearance for 30-millimeter tires—and aren’t sure of where your gravel exploration might stop. Better to experiment with what your current bike offers and then add a gravel bike if you want to get into wilder terrain.
For Pickman, the difference comes down not just to what you want to do with the bike, but how you want it to feel. That’s what settled it for my friend Dan as well. He wanted a bike with the efficiency and responsive ride of his old R5, but still capable of exploring dirt.
Ultimately, he went with a Canyon Endurace, which has the same claimed tire clearance as his R5. That was partly a function of the pandemic: Canyon was one of the few brands that had bikes ready to ship in weeks, not months. But Dan also liked that the Endurace’s geometry was more on the road side of the all-road spectrum yet could still handle some bigger tires. Something like the Cervelo Caledonia or Trek Domane felt like a step too far away from his R5. (Canyon’s aggressive pricing didn’t hurt either.)
Around Denver he rides it mostly on pavement with the stock set of wheels and road tires. But he also spends time in the Sangre de Cristo Mountains of southern Colorado, where the dirt roads are rougher and wilder than the urban Front Range. So he bought a second pair of hoops and set them up with 32-millimeter Panaracer GravelKing SK tires, which measure out to 34 millimeters wide on the bike’s DT wheels—technically four millimeters wider than the Endurance’s rated tire capacity.
So far the rig has been mostly up to the challenge. The gearing is low enough for even steep climbs, and since Dan isn’t bikepacking, he doesn’t want for extra accessory mounts. After a couple of rides bouncing over washboards, he’s learned to trust the lower pressures that are possible with wider tires.
In fact, he’s having so much fun on dirt that he bought a gravel bike: a Litespeed Watia, with clearance for 45-millimeter rubber, or up to 53-millimeters if you use the smaller 650b wheel size. It features a few more mounts for fenders, a top-tube bag, and three bottles, but no rack or frame bag bosses. Regardless, he has no regrets about his Endurace purchase, because it’s still a great bike for road and light dirt.
That’s what’s so great about all-road. It’s a gateway for a lot of riders, the perfect bridge between road performance and adventure capacity—between what you’ve always done on a bike, and what you might want to do next.