Buying A Used Bike On Carousell: 12 Things To Check

A used bike is usually a good buy. The risk isn't that the whole bike is bad — it's that one or two expensive components are worn out and you don't find out until you've handed over the cash. Here's what to actually put your hands on before you do.

Before You Meet

Ask three questions over chat: how long they've owned it, when it was last serviced, and where it's been stored. The storage answer matters more here than almost anywhere — a bike kept on an open HDB corridor for two years has had a very different life to one kept indoors, regardless of how it photographs. Ask for a photo of the drivetrain, not just the whole bike.

Also ask for the frame serial number and any purchase receipt. A seller who has both is a seller worth meeting.

The 12 Checks

Roughly in order of how much it costs you to get it wrong.

• 1. Frame, around the welds. Look for cracks, dents or ripples, especially where the top tube meets the head tube. This is the only check that's a hard no — a cracked frame ends the conversation.
• 2. Headset play. Hold the front brake, rock the bike forward and back. A knock you can feel through your hand means the headset bearings need attention.
• 3. Bottom bracket play. Grab a crank arm and push it side to side, not around. Any lateral movement or grinding when you spin it means bearing work.
• 4. Chain wear. Lift the chain away from the front chainring at the three o'clock position. If you can pull it clear enough to see daylight under a tooth, the chain is stretched — and a stretched chain has usually taken the cassette with it.
• 5. Cassette teeth. Look at the profile side-on. Teeth should be symmetrical triangles. Hooked or shark-finned teeth mean replacement.
• 6. Wheels, spun. Lift each wheel and spin it. Watch the gap at the brake pad or frame — a wobble side to side is a buckle. Squeeze pairs of spokes; any that feel loose compared to their neighbours mean the wheel needs tensioning.
• 7. Rim sidewalls (rim brakes only). Run a finger along the braking track. A visible concave dip means the rim is worn out and needs replacing, which is a wheel-level cost.
• 8. Rotors and pads (disc brakes). Rotors should be flat and evenly coloured. Pads with less than about 1.5mm of material left are due. See our brake guide for what the noises mean.
• 9. Tyres. Check for cracking in the sidewall rubber, not just tread. Tyres perish with age and heat here even when barely ridden.
• 10. Cables and housing. Look for splits, kinks and rust at the cable ends. Cheap to replace, but a sign of outdoor storage.
• 11. Seatpost. Ask the seller to raise and lower it. A seized seatpost is a genuinely miserable job and occasionally unrecoverable.
• 12. Ride it. Shift through every gear, brake hard from speed, and listen. Creaks under pedalling load usually come from the bottom bracket.

Cheap To Fix Versus Expensive

Cheap consumables — chain, cables, brake pads, tyres, bar tape. Use these as negotiating points, not reasons to walk.

Moderate — cassette, chainrings, a wheel true and tension, bottom bracket or headset service. Worth factoring into your offer.

Expensive — wheels, worn rims, a full drivetrain replacement, anything hydraulic that's been neglected. If two or more of these are due, the bike is worth less than it looks.

Budget For The Service

Almost every used bike needs something. A bike that's been stored unridden for a year typically needs brakes and gears properly set up — that's the Safety Package ($68). If the drivetrain is gritty or the bearings feel rough, the Premium ($148) or Gold ($198) tiers cover the strip-down. Building that into your offer is more realistic than assuming it's ready to ride.

Full detail of what each tier covers is in our 2026 price guide.

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