Used bikes are the best value in cycling. They're also where the most expensive surprises hide. Here's what to look for before you hand over money.
1. The frame — cracks and alignment
The frame is the only part you can't easily replace. Inspect:
- Joints and welds (aluminium): look for cracks, especially around the bottom bracket and head tube.
- Tubes (carbon): tap gently — a dull thud indicates damage. Look for scratches deep enough to expose weave.
- Dropouts: where the wheel mounts. If they're bent, the wheel won't sit straight.
- Alignment: sight down the top tube. The frame should be symmetrical.
A cracked frame is a dealbreaker unless you're paying pennies.
2. Wheels and hubs
Spin the wheels slowly. Watch for:
- Lateral wobble at the rim (truing is fixable; a wobbly hub is not).
- Bearing roughness — pull the rim side to side. Any play means new bearings.
- Tyre condition — cracks, cuts, tread wear.
- Spoke tension — ping each spoke with a fingernail. They should sound similar.
3. Drivetrain wear
The drivetrain is where most of the money hides. Check:
- Chain wear: use a chain checker or measure 12 links. If it's stretched past 0.5%, the cassette and chainrings are likely worn too.
- Cassette teeth: they should be square and symmetric. Hooked or shark-finned teeth mean replacement.
- Chainrings: same — look for asymmetry or burrs.
- Shifting: ride it. Shifts should be crisp at every position.
A worn drivetrain is $150–$500 to replace, depending on the groupset tier.
4. Brakes
- Rim brakes: pads should have material left; rims shouldn't be concave.
- Disc brakes: pads should be thick, rotors straight, and levers should feel firm (not spongy).
Bleeding hydraulic brakes is $60–$100 per brake at a shop.
5. Bearings everywhere
Feel for play in: - Headset (turn the bars with the front wheel off the ground) - Bottom bracket (rock the cranks side to side) - Wheel hubs - Pedals
Any grinding or roughness = bearings need replacement.
Bonus: the paper test
Ask the seller for: - Original receipt (proves it's not stolen) - Service history (proof of maintenance) - Warranty transfer (some brands allow it)
No receipt = walk away.
Use VeloMarto's protection
Every purchase through our Buy Safely service is covered — if the bike arrives materially different from the listing, you're protected. Sellers who list accurately have nothing to hide.