Locks and Security

Which type of bike lock should I buy?

A D-lock is the standard for street parking: rigid, hard to lever, and quick to use if the shackle reaches your frame, wheel and the stand. A chain with a hardened link is heavier but wraps around awkward railings and lets you lock a bike further from the anchor. Folding locks fold flat into a frame mount and give more reach than a D-lock for less bulk than a chain, at generally lower resistance to bolt croppers. Cable locks are for securing a wheel or saddle to a stronger lock, not for holding a bike on their own.

What do Sold Secure ratings mean?

Sold Secure is the UK rating scheme insurers usually reference, and it grades a lock by how long it holds up against a defined set of tools. Bronze suits a low-risk shed, Silver a short daytime stop, Gold a bike left in a city centre, and Diamond the highest tested level. The rating applies to the exact model tested, so check the name on the lock body rather than the brand — the Kryptonite New York and Kryptonite Evolution lines sit at different levels, as do the tiers within Abus and Hiplok ranges. If your insurer specifies a rating, buy to that.

What should I check on a used bike lock?

Open and close it several times with the key. A sticky lock cylinder, a key that needs jiggling, or a shackle that doesn't seat cleanly into the crossbar means the mechanism is worn or corroded, and a lock that jams while you're out is as bad as no lock. Count the keys — most come with two or more, and a lock with one key is a lock you'll be cutting off eventually. Check for cut marks, file scoring or drill dimples around the cylinder and shackle shoulders, which suggest a past attack. On chains, check the fabric sleeve for tears and the links for rust; on folding locks, check every rivet at the joints for play, since the joints are the weak point. Never buy a lock without keys.

Is a used bike lock worth buying?

Yes, if it comes with keys and a rating you can verify — the hardened steel in a D-lock or chain doesn't degrade much with age, so a well-kept Gold-rated lock is close in function to new at around half the price. That makes second-hand a good route to the heavy, expensive locks people flinch at buying new. Buy new instead for anything you'll register for a lock guarantee, since those schemes usually need proof of purchase and a first owner. Also buy new if the price is close: the saving on a budget cable lock is a couple of pounds and not worth the unknown history.

Where does the lock go if I'm carrying luggage?

A heavy chain rides better in a pannier or on a rack than on your back, and a D-lock in a frame mount rattles less than one wedged in a bag. If you're building a commuting setup, work out the lock, the bags and panniers and the rack together, because a full pannier and a 2kg chain change how the bike handles. Ground anchors and shed locks are a separate purchase and are usually sold with the bolts and resin fixings needed to fit them.