Locking a Bike at Work Without Losing It by Friday

This is written to be used rather than admired. Each section below is a decision about bicycle security, and each one has a default.

How bikes are actually taken

Most thefts are opportunistic and fast, using bolt croppers, a small angle grinder or simply lifting an unsecured bike. Cable locks offer very little resistance to croppers, which is why they are best used only as a secondary deterrent.

Portable angle grinders have changed the picture considerably, since almost any lock can be cut given enough uninterrupted time. That shifts the question from whether a lock can be defeated to how long it takes and who is watching. A thief choosing between bikes in a rack will take the one that costs them least time and attention.

What you lock to

A lock is only as good as the anchor, and bikes are routinely stolen by lifting them over a post or unbolting a rack. Check that the stand is fixed into the ground, that a post cannot be lifted from, and that a railing cannot simply be unscrewed.

With a loaded rack, scaffolding, signposts and drainpipes all look adequate and frequently are not. Position the bike so the lock is hard to attack, ideally with the shackle filled by the frame and the stand and no gap for leverage. Keeping the lock off the ground makes it harder to strike or lever against a hard surface.

Securing the parts that come off

Wheels and saddles with quick-release levers are removable in seconds and are stolen frequently even when the frame survives. Lock the frame and rear wheel with the primary lock, and use a second lock or a cable for the front wheel. Security skewers and locking bolts replace quick releases and are a cheap one-off change for a bike parked in public daily.

Take lights, computers, pumps and bags with you, since anything unsecured on a bike is effectively left on the street. A saddle secured with a loop of old chain through the rails is crude and effective.

Two locks and why

Different lock types resist different attacks, so a hardened shackle lock plus a chain forces a thief to carry two sets of tools. It also doubles the time required, and time is the resource thieves have least of.

Carrying two locks is heavier, which is a real cost, and it is the trade most riders make once they have lost a bike. Rating schemes run by insurers and testing bodies exist in several countries and give a rough comparison between products.

Match the lock spend to the bike's value and to how long it stands unattended, rather than to a general rule.

Location and habits

Busy, overlooked places with passing footfall are better than quiet corners, because attacks in view get interrupted. Covered and monitored parking at a workplace is worth asking for, and many employers will provide it when asked.

Vary nothing about a bike that stands in the same place every day for months, except perhaps the bike itself if it is valuable. Consider keeping a deliberately unremarkable bike for commuting and leaving the nice one at home. Bikes are stolen from inside sheds and communal hallways too, so lock it at home to something solid as well.

Frames, sizes and riding positions vary enormously; borrow before you buy wherever you can.

Before and after a theft

Photograph the bike, record the frame number, and register it with any national or community scheme available where you live. Keep the receipt, since insurers and police both ask for proof of ownership and value. Report a theft promptly and give the frame number, because recovered bikes are frequently unclaimable without one.

By the second week of riding, check second-hand marketplaces in the following days, and report rather than confront if you find it. Check whether your home contents insurance covers bicycles away from the property, as many policies do not without an extension.

The takeaway

Buy time, not certainty — solid anchor, two lock types, and nothing left on the bike.

The bike you ride daily beats the better bike you keep indoors.