Why buy used?
A used bike costs 40 to 60% less than new. With a good eye, you can find a bike for €1,500 that was worth €3,500 new just 2 years ago. But a bad purchase can cost more than a new bike once repairs are done. This guide teaches you to spot the good deal from the scam.
The 15-point inspection checklist
The frame (points 1-4)
1. Cracks and structural damage. Inspect each tube under raking light. On an alloy frame, look for cracks at joints (welds). On a carbon frame, tap lightly — a dull or hollow sound indicates internal delamination. Beware of bikes with "just a small cosmetic knock" on carbon.
2. Frame alignment. Look at the bike from behind: the rear wheel should be perfectly centered in the chainstays. A bent frame (crash) is irreparable in alloy and often in carbon.
3. Headset play. Squeeze the front brake and push the bike back and forth. A clunk or play indicates a worn headset (€20-50 repair) or a damaged frame.
4. Bottom bracket (BB). Spin the cranks by hand. They should spin freely, with no creaking or lateral play. A worn BB costs €30-80 parts + labor.
Wheels (points 5-7)
5. True. Spin each wheel and watch the gap between the rim and brake pads (or caliper). A slight wobble (1-2 mm) is easily trued. A major wobble (> 3 mm) indicates a damaged rim or broken spokes.
6. Spokes. Squeeze spokes in pairs — they should have similar tension. Loose or broken spokes = wheel rebuild (€60-100).
7. Tire condition. Check tread wear and sidewalls. Cracking on sidewalls = tires to replace (€30-80 per pair depending on range).
Brakes (points 8-9)
8. Pads. Disc brake pads should have at least 1 mm of material. Rim brake pads shouldn't be smooth. Replacement cost: €15-40.
9. Rotors. Rotors shouldn't have deep grooves or visible warping. A worn rotor costs €20-50 each.
Drivetrain (points 10-12)
10. Chain wear. Use a chain wear indicator (€10 tool). If wear exceeds 0.75%, the chain needs replacing (€15-40). If it exceeds 1%, you probably also need a new cassette (€30-80).
11. Cassette teeth. Look at the sprocket teeth: "shark fin" shaped teeth (asymmetric, pointed) indicate a worn cassette. Cost: €30-150 depending on range.
12. Shifting. Run through all gears, front and rear. Shifts should be clean, with no skipping or hesitation. Often just an adjustment, but a bent derailleur hanger (crash) costs €30-80 to replace.
Fork and suspension (points 13-14)
13. Fork stanchions (MTB). Check the stanchions (shiny tubes): no deep scratches, no oil traces. A leaking fork needs a service (€50-120).
14. Dropper seatpost. If the bike has one, check it goes up and down smoothly without excess play. A service costs €40-80.
The final check (point 15)
15. Serial number and theft. The serial number is stamped under the bottom bracket. Check it on BICYCODE (bicycode.org) or Bike Index to make sure the bike isn't reported stolen. Also ask for the original purchase receipt.
Where to buy used?
| Platform | Advantage | Risk |
|---|---|---|
| Troc Velo | Bike-specialized, detailed listings | Prices sometimes high |
| LeBonCoin / Gumtree | Volume of listings, good deals | Theft risk, little guarantee |
| Bike shops (trade-ins) | You can test ride | Limited choice |
| Decathlon Second Life | Inspected bikes, 1-year warranty | Limited range |
