2026 Colnago G4-X Shimano GRX Di2 825 2x

Archived: 2026 Colnago G4-X Shimano GRX Di2 825 2x · Cyclocross/Gravel · Published sizes: 450, 480, 520, 540, 570

• Confirm the frame markings and seller description match this archived model. Note every component that differs from the published build.
• Record the frame serial number. It should be legible, unaltered and consistent with the seller’s ownership history.
• Find the size marking on the bicycle and confirm the fit before judging the condition or price.

Archived: Frame: Monocoque carbon. · Fork: Carbon fork for disc brakes, external cables, section with round circumference · Carbon fiber

• Inspect the frame in bright light, especially the head tube, bottom-bracket area, chainstays and clamped surfaces. Look for cracks, ripples, crushed sections or signs of impact.
• Stand behind and in front of the bicycle to look for obvious frame, fork or wheel misalignment. Ask directly about crashes, transport damage and repairs.
• Inspect the fork crown, blades, dropouts and visible steerer area. Check that it is straight, securely installed and free of cracks or impact damage.

Archived: Group: Shimano GRX Di2 825 2x · Shifters: Shimano ST-RX820 · Front derailleur: Shimano GRX 2x: Shimano FD-RX820 · Rear derailleur: Shimano GRX 2x: Shimano RD-RX820 · Crankset: Shimano GRX 2x: 48-31T · Bottom bracket: ACROS T47 · Cassette: Shimano GRX 2x: 11-36 12v · Chain: Shimano GRX: Shimano CN-M8100 12V

• Confirm every shift battery charges and every control operates. Shift through the full cassette under light load while checking pairing, derailleur alignment and response at both ends of the range.
• Measure chain wear with a compatible gauge and inspect chainring, cassette or freewheel teeth. A new chain does not rule out wear in the remaining drivetrain.
• Turn the cranks slowly, feel for rough bearings and check for side-to-side play. Inspect crank arms, chainring bolts and pedal threads for looseness or damage.

Archived: Brakes: Shimano RX-820, 160 mm Front / 160 mm Rear, RT-MT800-S rotors

• Inspect pads and braking surfaces, check the complete cable or hose path, and confirm both controls feel consistent and return cleanly.
• Before riding, test every installed brake separately at walking speed. Each should stop firmly and release cleanly without its control reaching the end of its usable travel.

Archived: Wheels: Vision SC 45 Disc · Rims: Material: Carbon – with hooks; Rim Height: 45mm; Internal Channel Width: 21 mm · Hubs: Hubs with direct pull spokes · Front tire: Pirelli Cinturato Gravel 40 TLR · Rear tire: Pirelli Cinturato Gravel 40 TLR

• Spin both wheels and watch for side-to-side and vertical movement. Check spoke tension, rim condition and hub play. Inspect the carbon rims closely for impact marks, cracks, delamination or damage around spoke holes and bead hooks.
• Inspect both tire casings for cuts, cracking, plugs, bulges or exposed threads and confirm the installed sizes are safe for the rims and available frame and fork clearance.
• Remove and reinstall or closely inspect both wheel-retention systems. Axles or quick releases should tighten correctly with undamaged threads, hardware and dropouts.
• Confirm whether the bike is actually set up tubeless, whether both tires hold pressure, and when sealant and rim tape were last serviced.

Archived: Handlebar: CC.01 Wide integrated cockpitSizes 450Width: 400 mmSizes 480 -540Width: 420 mmSizes 570Width: 440 mm · Stem: Integrated cockpit (CC.01 Wide)Size 450 - 480Length: 90 mmSizes 520- 570Length: 100 mm · Seatpost: Carbon seatpost, 0.15 offset, "D-Shape" section · Saddle: NOVUS BOOST EVO Superflow FeC"Selle Italia" Model X BB FEC

• Apply the front brake and rock the bike to check for headset play or notchiness. Inspect the stem, handlebar and clamp zones, then confirm every fastener and control is secure.
• Check that the seatpost moves for adjustment and that the saddle, post and clamp hold securely without cracks, severe corrosion or damaged hardware.

• Before riding, confirm both wheels are secure, tires are safe, both brakes function, and the headset, handlebar, stem, cranks and pedals have no looseness.
• Begin at low speed. Test steering, braking and shifting progressively, then load the drivetrain and suspension only after the basic safety checks pass.
• Listen and feel for repeated knocks, grinding, skipping, brake pulsation or movement at joints. Stop the test if the bicycle cannot be controlled safely.