Mountain bikes and cyclocross bikes are for different things but often get used the same way.
For example, if your local mountain trail is like mine, I’m guessing you’ve probably seen an increase in the percentage of CX bikes compared to the number of mountain bikes.
But that doesn’t mean you can replace one for the other.
A cyclocross bike is designed for the harsh conditions of a cyclocross race and is better suited for light off-road riding. A mountain bike with deep tread tires, suspension, and multiple gears is designed for the more serious off-road, big rocks, and rooty terrain.
Another philosophical difference is that cyclocross bikes are designed to maintain contact with the ground, but not necessarily for MTBs.
Now, if you’re still undecided on what bike category to choose, read on.
I’ve had experiences with both cyclocross and MTB, and I’ll compare the two bikes for a more informed decision in the bike guide below.
What's a Cyclocross Bike?
Cyclocross is a drop-bar bike designed for use in cyclocross racing.
Typical cyclocross courses traverse muddy fields, grass, gravel, and sand.
Geometry-wise, a cyclocross is similar to road/gravel bikes but optimized for navigating the technical courses.
For example, they include knobbier tires than roadies and gravel bikes, taller sitting positions, and greater mud clearance for better navigation on obstacle courses.
The Cross bikes also incorporate technologies reserved for the more technical bikes, such as disc brakes and tubeless tires.
What’s a Mountain Bike?
As their name suggests, mountain bikes are designed for riding on the more rugged mountain terrains.
The mountain bikes have a more upright frame. The frame is sturdy and usually made of solid materials such as steel, aluminum, or carbon fiber.
Another distinct feature of mountain bikes is the knobby tires that provide better grip and traction on different technical terrains.
Mountain bikes aren’t suited for use on the smooth pavement, as they’re sluggish. However, they excel on technical terrains more than cyclocross bikes.
Their upright sitting position makes up for a more comfortable riding experience, especially under dirt tracks.
Comparing Cyclocross and Mountain Bikes
The section below will look at the similarities and differences between cyclocross and a mountain bike.
Hopefully, by the end of the guide, it’ll be easier for you to decide your choice of bike.
The idealness of a cyclocross bike or mountain bike varies greatly depending on the terrain you want to ride.
If you’re going to ride gravel or a cyclocross race, get a cyclocross bike. Conversely, go for a mountain bike to hit the technical trails and jumps.
But that’s quite superficial.
See, cyclocross also has a place on the dirt tracks.
For example, the single tracks with occasional roots and rocks aren’t a problem for cyclocross bikes. Hell, yeah, these tracks aren’t a problem for the road bikes either.
What you want to keep off with a cyclocross are trails with big drops. It’s not like it’s undoable, but you need to choose your line carefully. Otherwise, you might end up with a broken wheelset or break your teeth.
Cyclocross also has a higher average speed for the run-up sections than a mountain bike, so the ideal trails would need to be smoother, less twisty, and without jumps and drops.
On the other hand, a mountain bike will take on the technical terrains that would otherwise be a boneshaker for the cyclocross bikes.
The mountain bike will also plow through the muddy and rooty trails where your cyclocross peers would jog with their bikes on their shoulders or even with pinchy flats.
But don’t get me wrong; using a cyclocross on the dirt trails is fun but might be more draining and physically challenging.
I’ve done recreative mountain biking before turning to cyclocross, and I’ve had so much fun with my cyclocross bike on the not-so-technical terrains.
Otherwise, a technical terrain will beat up your cyclocross bike and end up with the bike on your shoulder running.
As we’ve seen above, cyclocross bikes are fun to ride on the flat-packed dirt and gravel roads, which most people call “mountain biking.”
But for the actual mountain biking and technical terrains, I don’t think so.
Many dense roots, rocks, and obstacles become an issue with a CX, especially if your bike handling skills don’t measure up.
For example, the local trails are a little more technical and super rocky here in Pennsylvania.
Riding a cyclocross bike on these trails is not fun. It’s not even about handling issues as it’s the comfort. After a couple of miles on these treacherous terrains, my shoulders and arms are usually beat up.
The rigidity of the cyclocross bike is also awful on the body, and with no suspension fork, you always feel like you’re about the break your bike and back.
On the other hand, I can push my mountain bike as hard as possible without being nearly sore or beat up as my cyclocross bike.
The big drops are also quite a breeze on a mountain bike, and generally, it doesn’t hurt pushing the mountain bike to the limit.
Both options are ideal winter bikes, but again, it’ll depend on the terrain and levels of snow.
I’ve a Fantom Cross with studded tires, and I had more fun on the road than on the local trails.
However, the snow was shallow, fresh, and on a lightly used trail.
But if your trails are covered in rutted icepacks from heavy winter use by other cyclists, I’d suggest you pick a mountain bike.
Of course, depending on your handling skills and energy, you could try a cyclocross. I once managed to use my Fantom cross on the rutted trails but came home with aching arms and shoulders from the constant balance adjustments.
The wheels had less grip and were slipping all over, while traction was negligible.
In short, I’d recommend a cyclocross bike for winter road biking and a mountain bike for singletrack winter use.
The snow level also influences what bike to get; when it’s nice, a cross bike will do, but I’d choose a mountain bike when the snow gets super deep and it’s icy.
A principal difference between a cyclocross and a mountain bike lies in their respective geometries.
My cyclocross has a similar setup to a road bike. However, it has a higher bottom bracket height to allow effortless jumping over obstacles.
A CX’s geometry is also more aggressive, like a road bike. While the body positioning is ideal for racking up miles, it’s not so comfortable over short distances or even navigating technical areas.
In particular, it’s not great for braking on the steep downhills.
On the other hand, a mountain bike has an upright sitting position.
The design isn’t nimble and sluggish on the paved and hard-packed dirt. Using a mountain bike on a repetitive corner for a cross race that requires quick acceleration, tight turns, and slowing down rapidly sucks.
However, if you need the stability and ease of handling on the really technical terrains and off-road riding, you can’t really go wrong with a mountain bike.
The upright position allows a mountain biker to see and “read” the terrain ahead much better while allowing you to blast over any obstacles.
Uphill and Downhill Riding
Cross bikes do a lot, and I’ve even used them on the mountain trails. But one of their limitations is the low gears.
The gears on Cross bikes aren’t low enough for the really steep grades.
On a mountain bike, you can climb anything. Along with the wide-range gearing and longer wheelbase, mountain bikes also have wider and knobbier tires that grip like claws.
I hardly get stuck on punchy climbs and long sinuous ascents on my Santa Cruz Tallboy, and I swear the mountain bikes love to climb.
Of course, for the not so steep mountain climbs, the cross bikes will climb fast. Sometimes, when I ride with my MTB friends, they’re surprised at how effortlessly and fast I climb.
But once the gradient rises, things become sketchy. I’ve to walk or shoulder the cyclocross bike uphill.
Downhills aren’t any different either. Bombing down some single track isn’t fun, especially when you don’t have a front suspension.
Riding downhill on a cyclocross bike can sometimes get hairy without suspension and disc brakes. I’ve dislocated a shoulder riding downhill on my Fantom Cross when the cantilever brakes failed me.
Unless you’re dedicated to mountain bike races, a cyclocross would fit you.
See, cyclocross is simply road bikes that fit wider tires, and this makes them ideal for most recreational riders and the imperfect gravel roads and cross races/gravel races that most riders are often on.
Simply put, a cyclocross is a bike that kicks ass on the road and handles the light dirt trails.
On the other hand, a mountain bike is specifically designed for rugged use. It’s meant to navigate the harsh and rugged mountain terrains while blasting through obstacles.
Comfort depends on the type of terrain but also on the suspension.
Mountain bikes, especially full suspension bikes, are more comfortable and forgiving.
In fact, when I got back from my knee injury, I picked my Santa Cruz but kept to short distances.
Again, if you’re planning to take on the singletracks, I would also suggest a full-suspension mountain bike to save you from the wear and tear on your body.
The cyclocross bikes are fun but quite stiff. Their rigidity may take a toll on your body, especially if you’re doing hardcore road ride on sections with obstacles.
I mostly do mountain biking, but I’d suggest you get across if you need the versatility to navigate different terrains.
Of course, a mountain bike will take you to places where a cyclocross can’t even dream about, but cyclocross is a good middle ground and extremely versatile.
You can use a cyclocross bike all day on the road with some slick tires and navigate the fire roads and canal paths pretty well.
On the other hand, a mountain bike will hold you back on the road when you need to participate in a group ride with road racers.
I’ve also done a cyclocross race on a mountain bike, but it’s a disadvantage on most courses. At some point, when cross racing, you even stop seeing the mountain bikes.
Cyclocross is also flexible enough to do most types of riding. I simply swap the different tires on my Fantom Cross and do most types of riding.
An MTB may also have a marginal edge over the cyclocross in the city because of the more upright riding position. It gives you a better view of the traffic.
But for the longer rides, I’d prefer the CX’s drop-bar handlebars/drop bars, similar to those on a commuter bike. The multiple hand positions are less fatiguing for long-term use, and the aerodynamic position reduces drag and wind resistance.
Cyclocross bikes are also a great option for singletrack use. Depending on the terrain, it may be physically demanding but fun compared to a dual-suspension mountain bike.
Generally, a cyclocross has quite a bit of functional overlap with many other bike categories, much more than an MTB.
This is a no-brainer.
A cyclocross bike is the kings of the road, next to a road bike and a gravel bike.
Riding a cyclocross will be more fun than riding a mountain bike on any fast and flat trail.
A cyclocross feels “racey,” precise, and fast, just like the road bikes.
The slick and narrow tires have a low rolling resistance, and the limited contact patch with the ground reduces the riding friction.
Plus, they also have an aerodynamic sitting position, so you’re less likely to feel the wind resistance or anything.
Of course, how fast your bike goes will also depend on the terrain
An MTB will have marginal speed gains over the road bike/gravel bike on the rugged singletracks. An MTB will simply blast over any obstacles while a cyclocross bike tries to get through the debris.
But other than the rough terrain, an MTB can never match a CX, speed-wise.
Of course, I’m not super concerned about speed, but I’d also love to keep up with the others!
Cyclocross bikes have slicker and skinnier bike tires than mountain bikes.
Usually, the tire width range for a cyclocross bike is 35mm.
The Cyclocross race bike tires are generally useful for pavement and light off-road use.
They’re not as stable as the mountain bike tires, and the truth is you’re likely to fall more often on a CX than on your MTB.
You’ll also feel every rock on the trail and walk because of pinch flats.
On the other hand, the MTB tires are wide, bulky, and stand up to anything on the road. They also work on sand, snow, and other loose off-road surfaces.
Unfortunately, the extra weight also means they’re sluggish, especially on hard surfaces and pavement.
One of the benefits of my Fantom Cross over my Santa Cruz is the ability to dismount and carry!
CX bikes are generally lighter and hardly get on stuff or feel awkward to ride.
Unlike my MTB, navigating by foot with the CX on my shoulder is pretty easy.
A cyclocross or mountain bile will ultimately depend on your cycling needs/purpose and type of terrain.
If you need a bike for cyclocross races or light off-roading, a cross bike is a superb choice.
Cyclocross bikes make an inspiring pick for riders looking for an “off-road” bike but with the capabilities of a gravel bike or road bike. It’ll excel on the pavement and hard surfaces, more like the gravel bikes.
Equally, it has an aerodynamic geometry that will allow you to rack up miles of cyclocross racing and road racing without fatigue.
On the other hand, a mountain bike is an incredible option for riders oriented toward the more technical mountain terrains and riding off-road.
They’ve wider clearance and will climb the steep with relative ease.
Overall, an MTB is ideal for rough and rugged use.