Colnago G4-X Frameset

Colnago has spent more than seven decades building bicycles that win races — from the cobbles of Paris-Roubaix to the mountain stages of the Tour de France. The Colnago G4-X Frameset carries that institutional knowledge into a discipline that demands something different: not pure speed on clean tarmac, but the ability to hold pace across hours of mixed terrain, loose climbs, and roads that stop being roads altogether. This is a purpose-built gravel frameset, developed to meet the specific structural and geometric demands of performance gravel riding rather than adapted from an existing road platform. The carbon layup reflects what Colnago has learned building frames for WorldTour teams — tuned deliberately rather than uniformly. Through the bottom bracket and chainstays, the frame is designed to be stiff, translating pedaling input into forward motion without flex bleeding off your effort. Through the seatstays and fork, there is a degree of engineered compliance that takes the sustained edge off rough surfaces — not suspension, but a frame that absorbs enough to keep you riding hard when the terrain turns punishing. The geometry sits where competitive gravel riders will feel immediately at home: stable and planted at pace, with enough front-end responsiveness to handle technical sections without demanding constant correction. Internal cable routing protects your housing from the grit and debris that gravel riding guarantees, and keeps the cockpit clean regardless of what groupset you build it up with. Flat-mount disc brake compatibility opens the G4-X to virtually any modern hydraulic setup, from electronic shifting systems to more traditional mechanical configurations. The tapered head tube stiffens the front end where precision matters most — at speed, on loose descents, in corners where confidence in the frame beneath you is not a luxury. Available in five sizes from 45cm to 57cm, and two colorways — ICBL and PIGR — the G4-X offers genuine fit range without forcing compromises at either end of the size run. Colnago G4-X Frameset Specs at a Glance Frame Material: High-grade carbon fiber Discipline: Performance gravel racing and mixed-terrain riding Cable Routing: Internal, full-length Brake Mount: Flat-mount disc Head Tube: Tapered Available Sizes: 45cm, 48cm, 52cm, 54cm, 57cm Colorways: ICBL, PIGR Axle Standard: Thru-axle Groupset Compatibility: Modern hydraulic disc groupsets Included: Frame and fork (frameset) Design Benefits Targeted Carbon Tuning: Rather than applying a single carbon layup across the entire frame, the G4-X is designed with distinct stiffness characteristics in different zones. The drivetrain-side of the frame — bottom bracket shell and chainstays — is built to resist flex under load, so your power goes to the rear wheel rather than into the frame. The upper portions of the rear triangle and fork are allowed to move slightly, cushioning the high-frequency vibration that accumulates over long gravel days. Gravel-Specific Geometry: The G4-X was not derived from Colnago's road geometry and adjusted — it was developed specifically around the demands of gravel racing. The result is a riding position that keeps you stable and efficient on long efforts while still giving you the front-end responsiveness needed when terrain demands quick reactions. It suits riders who want to move fast all day without sacrificing control on technical ground. Clean, Protected Drivetrain Integration: Full internal cable routing means housing runs through the frame rather than along the outside, keeping brake and shift cables away from the debris that gravel generates. Beyond aesthetics, this directly extends the service life of your cables and housing and reduces the friction that builds up when grit works its way into external guides and stops. Flat-Mount Disc Compatibility: Flat-mount disc brakes have become the standard for performance gravel and road framesets, and the G4-X is built around that standard. This means you can pair the frameset with calipers from any of the major groupset manufacturers without adapters or workarounds — a clean interface that keeps weight down and gives you genuine choice when speccing the build. Tapered Head Tube Stiffness: The tapered head tube accepts a larger-diameter lower bearing, which stiffens the junction between fork and frame where torsional loads are highest. On gravel — where you are constantly making small steering corrections over uneven surfaces — this translates to more precise handling and less vagueness at the front end, particularly when descending at pace or cornering on loose surfaces. Final Take The G4-X is built for riders who take gravel seriously — those who want a frameset that reflects genuine engineering intent rather than a road frame with relaxed angles and wider tire clearance. It suits competitive gravel racers, bikepacking riders who push hard on mixed terrain, and anyone who wants to build a high-performance gravel bike around a frame that Colnago developed with the same rigor it brings to its road lineup. If you know what you want in a build and you want the frame to match your ambitions, the G4-X is the foundation to start from.