Gravel bike vs mountain bike: Which is best?

Club runs and cafe stops around the world are filled with debates about cycling’s biggest topics. It could be disc brakes versus rim brakes. Carbon versus aluminium. In recent years, few topics have been as divisive as gravel bikes.

Gravel bikes are relative newcomers to the cycling scene. People have been riding bikes off road for decades, but 'gravel riding' as we know it started in the USA not long over a decade ago. It has since exploded onto the global stage, and now gravel bikes, gravel routes and gravel riders are everywhere.

Like all new things, gravel has been met by a certain amount of friction, especially among traditionalists. Many people question whether 'one more bike' is really necessary — we already had road bikes and mountain bikes, after all.

Whilst road cyclists are coming around to the idea, a lot of mountain bikers are on the fence. As far as they're concerned, there's nothing a gravel bike can do that a fast cross-country bike cannot.

In fact, we've tried to prove to our GMBN counterparts that the gravel bike is the best all-round off-road machine several times, to no avail.

Not one to be deterred, Si Richardson took GMBN's Isaac Mundy on a challenging 120km route around Somerset, England, to prove once and for all that gravel bikes are best for mixed-terrain riding.

For the challenge, Si’s steed was the Canyon Grizl, already battle-hardened in multiple other challenges, including his attempt to conquer the 640km Further East ultra-endurance race.

Isaac opted for the Mountain Bike World Cup tried-and-tested Canyon Lux, a mountain bike built for speed. We should also mention that Isaac is a former pro-level road rider and still regularly podiums at national-level crit races — we thought we’d get our excuses in early!

• Read more: Gravel vs road: how much slower is a gravel bike?

So which is best?

Gravel bike vs mountain bike is a test we've done before, but this time, the length of the challenge really shone a light on the gravel bike's strengths. A cross-country bike can keep up with a gravel bike without issue, but when the hours tick by, though, most riders would find the body position and reduced rolling resistance of the gravel bike add up to make the day more relaxing and comfortable.

As our mountain biker Isaac put it, "it takes going out for a whole ride for the gravel bike advantages to come out".

"It's just these little accumulative advantages over 100km that means your elbows and your wrists and your shoulders and your back and your knees everything is just a bit better supported."

Granted, there will always be a few moments in the day when the mountain biker has more fun. Inevitably, there will be a steep descent or unusual obstacle that the mountain biker will fly through while the gravel rider picks their way across carefully.

But when you're riding for a long time, covering big miles, those kind of instances are few and far between. As Isaac said himself after completing the ride:

"It was ten seconds over a five, six-hour ride — the ratios aren't there."

The width of Isaac's bars was a hinderance too. Of course, they made his body position less aerodynamic, and the wrist angle wasn't as comfortable as the hoods of a drop-bar bike. More practically, though, on narrow countryside paths, Isaac found that his bars meant his hands snagged on brambles and obstacles through the day.

So is a gravel bike better than a mountain bike? For long, non-technical mixed-surface rides, yes. They're faster and they're more comfortable. Of course, the cross country mountain bike has its place, but for the kind of riding that a lot of us do, the gravel bike is the perfect tool for the job.

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