Types of lock

D locks

These are rigid steel locks in a D or U shape, generally very heavy and tough-looking. The more you pay, the stronger and more secure it will be. D locks range from around £20-£80. They can be heavy (often over 1kg), although many come with a mounting bracket so that you can attach your lock to your frame whilst riding. They can be limiting in that they will not fit around all street furniture, for example lamp posts.

When you lock up, try to fit the stand, the rim of one of the wheels and the frame in the D. By securing your wheel as well you’ll not only make it harder for thieves to take, but there’ll also be less space in the D which will prevent thieves from inserting bars or jacks into the space to lever the lock open. It’s best to angle the lock so that the opening is facing down. This prevents thieves from pouring in substances such as glue to prevent the owner from being able to retrieve the bike, giving them the chance to force the lock open later.

Cable locks

Cable locks can vary enormously in weight and strength. They are more flexible so can be used in situations where a D lock might not fit, but thinner, cheaper versions are very easily cut through. However, thicker cable locks can be very secure.

Thinner cables are useful in combination with other locks to secure parts like wheels or your saddle so that you don’t need to remove them every time you leave your bike.

Chains and padlocks

These can be very heavy and impractical to cart around, but they are very tough and a good quality hardened heavy-duty chain combined with a couple of very good hardened padlocks may be the strongest option available. If you need to leave your cycle locked up outside somewhere regularly you might consider leaving your chain locked there permanently (though please keep in mind inconvenience to other users).