Bicycles in India don't carry registration certificates the way two-wheelers do, but a legitimate sale still leaves a paper trail. Ask for the original purchase invoice or the bike shop's billing record — it confirms the model, the year, and roughly what was actually paid, which is useful both for negotiating and for warranty transfers on frames that carry one (several carbon frame brands sold in India offer multi-year frame warranties that can transfer to a second owner with proof of purchase).

If a seller can't produce any proof of purchase at all and the bike is a higher-value model, ask why. It doesn't automatically mean anything is wrong, but it removes your ability to verify the bike's history, and it's worth factoring into the price you're willing to offer.

Inspect the frame in direct daylight, not a dim garage — carbon cracks and aluminium dents are both far easier to miss under artificial light. Run a finger and eye along the top tube, down tube, seat stays, and especially the chainstay-to-bottom-bracket junction, which takes the most stress on a bike that's been crashed or dropped. On carbon frames, look for spider-web hairline cracks, a dull or "crushed" patch in the clear coat, or any area that looks like it's been touched up with paint that doesn't quite match.

A frame you can't confidently assess for structural damage yourself is worth a paid inspection at a bike shop before you buy — a cracked carbon frame is a safety issue, not a cosmetic one, and it can fail without warning under load. This is the one check on this list worth spending money to get right rather than guessing.

Check the derailleur hanger — the small replaceable bracket the rear derailleur bolts to — for visible bending. Hold the rear wheel and sight down the cassette from behind the bike; if the derailleur pulley wheels don't line up parallel to the cassette, the hanger is likely bent, which is a cheap fix but confirms the bike has had at least one hard knock.

1. Check chain wear with a chain checker or the "12-inch" test. Measure 12 inches (24 links) along the chain with a ruler — if it measures noticeably longer than 12 inches, the chain has stretched and has likely already started wearing the cassette and chainrings with it, which are far more expensive to replace.
2. Look at the cassette teeth from the side. Worn teeth develop a hooked, shark-fin profile instead of a straight one. A hooked cassette paired with a new chain will skip under load.
3. Spin both wheels and watch for wobble. A wheel that wanders side to side as it spins needs truing at minimum, and may indicate a bent rim if the wobble is severe.
4. Squeeze both brake levers hard. Check pad wear through the caliper, and on hydraulic disc brakes, feel for a lever that sinks slowly to the bar — a sign of air in the system or a leaking seal.
5. Test every gear, under load if possible. Skipping, hesitation, or a chain that won't sit on the smallest or largest cog cleanly points to a derailleur or hanger issue, not always a quick fix.

Never skip the test ride, even for a five-minute loop around the block or a car park. Listen for creaks under pedalling load, feel for a headset that clunks under braking, and check that the saddle height suits you reasonably well — a huge mismatch in frame size isn't something a stem or seatpost swap can always fix.

Use whatever you've found as leverage, not as a reason to walk away automatically. A stretched chain, a hairline in the paint that turns out to be cosmetic, or worn brake pads are all normal wear that a fair price already accounts for — point them out and negotiate down rather than treating every flaw as a dealbreaker. Reserve walking away for the frame-integrity and hanger checks above; those aren't negotiable, they're pass or fail.