The Colnago G4-X has a clear place in the Italian brand’s range: performance-focused gravel. Not a travel bike. Not a utilitarian gravel loaded with mounts. Nor a bike meant to go get lost on overly technical singletrack.
No, the G4-X aims for something else: riding fast, for a long time, on mostly rolling gravel routes, with that ever finer line between a road bike and a light off-road bike.
And inevitably, since Florian Vermeersch’s world title in 2025 on this model, the bike has gained an extra layer of legitimacy. It’s not just a catalogue “race” gravel. It’s a bike that has won at the highest level of the discipline.
Highlights:
- Very stable at high speed
- Good balance of stiffness, comfort and stability
- Deep, beautifully executed colourway
- Campagnolo Super Record X groupset perfectly in tune with the bike
To improve
- No internal storage
- GPS mount could be better
The test bike here uses the same colour as the world champion’s bike. A deep green, really well done, with small fir trees on the fork and the seatstays. It’s nicely executed and gives the bike real presence.
On the other hand, I’m a bit torn on the link with Colnago’s identity. The mountain/gravel effect works visually, but you don’t necessarily find that historic Italian touch we spontaneously associate with the brand. It’s a detail, but on a Colnago, details matter.
A well-thought-out frame, but not as complete as expected
On the frame, the G4-X offers the essentials for a modern, sporty gravel bike. There are two mounting points on the top tube, neatly hidden under a very clean little cover. Under the down tube, two additional mounts let you add a bottle cage or a small cargo solution.
And then, it almost stops there.
No internal storage. No multiple bottle cage positions to precisely adjust placement based on bags or frame size. No mounts on the fork. On that last point, it’s not really shocking: the G4-X isn’t designed for hardcore bikepacking, and adding mounts everywhere would have blurred its positioning.
The most regrettable part is the lack of internal storage. In 2026, even on a performance bike, this kind of solution makes sense. Not to carry your house, but to stash a tube, a tubeless plug, a CO2 cartridge or a multi-tool without multiplying visible accessories.
It’s not a deal-breaker. But on a bike of this standing, we’d like Colnago to push practical integration a bit further.
The T47 bottom bracket, on the other hand, is a very good thing. It’s coherent, modern, mechanically reassuring, and quite welcome on a bike meant to handle mixed demands between fast road and paths.
A very road-focused cockpit, but consistent with the brief
The G4-X comes with a Colnago in-house cockpit that leans more towards road than adventure gravel. The width remains contained, the position is sporty, and the whole setup fits the bike’s programme well.
It’s not the most reassuring cockpit for slow, technical riding, but that’s not what this is about. On the road, on fast tracks, on rolling paths, this approach makes perfect sense.
You get that crossover idea again: a gravel bike able to speak to road riders without yanking them out of their comfort zone.
One point did disappoint me though: the GPS mount tends to slip. Again, not a big deal. But it’s precisely these little details that make the difference on a premium bike. When you buy a Colnago, you don’t just expect a good frame. You also expect the finish details and small touches that justify the brand’s aura.
Same comment for the lack of a clear torque spec marking in some areas. On a high-end carbon bike, that kind of information should be obvious, visible, reassuring.
On the trail: stable, fast, but not harsh
It’s ultimately out on the trail that the G4-X more than makes up for things.
I had a pretty simple concern before riding it: ending up on a gravel bike that’s too stiff, too demanding, too race-focused. An efficient bike, sure, but tiring as soon as the terrain gets rough.
That’s not the case.
The Colnago G4-X is stable at high speed, stiff enough to respond decisively when you push, yet it retains real comfort. It’s not a sofa, obviously. But for a performance gravel bike, the balance is very well judged.
With Campagnolo Bora X wheels, which are relatively stiff, the tested build wasn’t trying to soften the bike. Despite that, the G4-X remains composed, predictable, and not as demanding as you might imagine.
It makes you want to ride fast, without punishing you for every imperfection in the terrain.
On rolling sections, it carries speed very well. On the road, it behaves almost like a beefed-up endurance bike, especially if you imagine a more road-focused wheelset and suitable tyres. On paths, it stays composed, precise, and filters enough to maintain pace without tensing up.
A gravel bike built for Europe, not for the extreme
It’s important to understand the G4-X’s playground. This bike isn’t made for very technical, rough, slow, demanding gravel with sections that border on MTB territory.
It can go there occasionally. But that’s not where it shines.
Its sweet spot is fast courses, long tracks, white roads, rolling sections, the European events where you alternate between road, compact gravel and farm tracks. In short: exactly the kind of terrain you find at many current gravel races, including at the highest level.
In that light, its world title makes sense. The G4-X isn’t a spectacular gravel bike on the spec sheet. It doesn’t have huge tyres, a suspension, an ultra-wide handlebar or a stack of accessories. But it’s coherent for going fast on modern, rolling gravel.
Colnago states tyre clearance up to 45 mm. That’s not huge at a time when some gravel bikes go well beyond, but it’s still enough for the intended use. With 45 mm all-round tyres, the bike keeps a very composed behaviour. On the road, efficiency is inevitably penalised compared to faster race tyres, but the G4-X remains genuinely effective.
With a faster setup, there would probably be another notch to gain.
Campagnolo Super Record X: a build that fits perfectly
The test bike was equipped with the Campagnolo Super Record X groupset, which we reviewed separately. It’s hard not to mention it here though, as the groupset suits the G4-X’s spirit so well.
On an Italian bike, performance-oriented, with such a refined aesthetic, the pairing works very well. The groupset elevates the bike, both visually and in use.
The only real regret on this build: the 38-tooth chainring. For my profile and playground, that’s clearly not suitable. You end up too often on the last two or three cogs as soon as the speed picks up or the terrain becomes rolling.
On a gravel bike like this, which naturally encourages you to keep the pace up, more ambitious gearing would have made more sense. That’s not a criticism of the frame, more a reservation about the specific build we tested.
Beyond that, nothing to complain about: the groupset works very well and further reinforces the bike’s premium character.
My take on this Colnago gravel bike
The Colnago G4-X is a very good performance gravel bike. Not because it ticks every current box, precisely. But because it stays coherent with its programme.
It’s fast, it stays stable, it filters better than its positioning suggests, and it doesn’t require you to be a pro to enjoy it. On a rolling gravel course, at a European event, or with a second wheelset to alternate road and gravel, it makes a lot of sense.
It’s not perfect. The lack of internal storage, a few functional finishing details and some equipment limits are reminders that Colnago could have gone further. At this level, you almost expect the details as much as the dynamic behaviour.
But once on the bike, the essentials are there. The G4-X rides true, rides fast, and makes you want to push.
It’s not the most versatile gravel bike on the market. It’s not the most adventurous either. But to ride hard on the right terrain, it clearly deserves its status.
