> Our review guidelines
Millions of bicycles are stolen in the US and Europe each year, so it’s always a good idea to carry a lock if you’re leaving your bike anywhere.
Trouble is, some locks are often cumbersome to carry.
This article tells you where to keep your lock while riding.
Types Of Bike Locks You Can Carry
There are three main types of lock you can carry on your bike.
U-Locks (D-Locks)
This type of lock is named after its resemblance to the letter “U” or “D”, depending on whether the crossbar is included in this likeness. The crossbar is the part holding the cylinder, which houses the lock mechanism.
U-locks are one of the securest ways you can lock a bike, though exactly how secure they are depends largely on the thickness of the shackle.
A 16mm shackle is extremely resistant to being cut by bolt croppers or bolt cutters (a favorite tool of opportunist bike thieves). At this thickness, a U-lock is regarded as bolt-cropper-proof, though manufacturers often prefer to say “resistant.”
Another desirable feature in U-locks is the double deadbolt. This means the shackle locks into the crossbar in two places and is thus harder to break open, particularly by leverage.
Expert lock pickers can pick almost any lock, but this does not account for the vast majority of bike thieves, who use cruder methods.
Some consideration should be given to the width between the shackles and the shackle length. A lock that is oversized or resting on the ground allows thieves more space to use and maneuver tools, which can be as basic as a hammer or crowbar.
You may need two U-locks if you have two quick-release wheels, unless you don’t mind resting the front of the bike on its forks (or have a way of protecting them).
Video: How NOT To Lock Your Bike
Chain Locks
The chief benefit of chain locks is their versatility. You can lock your bike to a wide range of objects and wrap the chain around them multiple times to reduce accessibility.
Chain locks are typically made with hardened steel links. They can’t be leveraged open like some U-locks and they’re hard to cut open even with bolt croppers or power tools. Of course, not all chain locks are equal.
Note that chain locks are inherently more vulnerable if you leave them dragging on the floor, as the thief can then use the ground to exert more power into bolt croppers. This applies mostly to lighter locks: the type you’re more likely to carry.
The main disadvantage of chain locks is their inherent weight, and the heavier they are, the more effective they are. U-Locks are appreciably lighter for the same level of security.
Like U-locks, a hardened chain lock is considered to be bolt-cutter-proof when the links are 16mm wide (each side). However, this makes for a very heavy chain, similar to those seen around motorbike wheels.
Video: How To Lock Your Bike
Cable Locks
Cable locks have many benefits, including their light weight, portability and low cost. They are made with many thin strands of steel, often encased inside a plastic tube.
Because they’re so light, you can buy cable locks in quite long lengths, too, which makes them more versatile. What’s not to like?
Of the three main locks, cable locks are by far the easiest to break. Many of them don’t even need bolt cutters; a thief can cut them open using ordinary, highly concealable wire cutters.
When you think about how cable locks are constructed, it’s hardly surprising that they’re easy to cut open. You’re cutting thin strands of wire, as opposed to the thick chunks of metal found on U-locks and chains.
With the above in mind, you can only use a cable lock with any confidence if the bike is in your vision the whole time, like if you’re popping into a convenience store. Even then, you’d be wise to lock up an expensive bike with something else.
Cable locks are less of a visual deterrent than thick chains or sturdy U-locks.
Combination vs Key Padlocks
Cable locks commonly use a combination mechanism for locking and unlocking. Be aware that keyed padlocks are more secure than combination locks.
Thieves can open many combination locks using nothing more than a thin metal shim, which they use to detect the position of the notch in each rotating disc. It’s also possible to open such locks by hand, merely by feeling resistance in the discs.
Any Other Lock Types?
Besides the main three types of bike lock, you can also buy folding locks. These are more portable than U-locks, lighter than chains, and generally more secure than cable locks.
Folding locks do not offer the same level of security as the better chains or U-locks, however, because they tend to be thinner and introduce more ways to be broken open (e.g., by drilling or shearing rivets).
Zip-tie locks with steel cores and combination mechanisms are also available. These are okay for a minute or two if you’re within constant sight of your bike, preferably if it’s also locked by another lock.
Video: Zip-tie Lock Limitations
The Best Places To Keep Your Lock While Riding A Bike
There are a number of different ways to carry a lock whilst riding your bike. The most common are described below.
Bike Mount Holder
Dedicated bike mount holders are ideal for rigid bike locks, as they hold them in one place without impeding your pedaling or unbalancing the bike in any way.
Typically, lock holders go inside or adjacent to the “triangle” of the frame, so they’re not always ideal if you’re using this space for something else (e.g., drink bottles).
Suitable for:
- U-locks of all sizes
- Folding locks
Read more: U-Lock mounts
Around The Seatpost
A classic way to carry a bike lock is to wrap it around the seatpost multiple times. This is convenient as long as you don’t have anything else fixed to it, like a rear light or cargo rack. For this method, the lock shouldn’t be either heavy or too long.
Suitable for:
- Cable locks
- Light chain locks
- Small U-lock
Around The Top Tube
An alternative to wrapping a lock around the seat post is to use the top tube instead. This doesn’t do much for aesthetics, but it works. Ideally you want to avoid having a metal padlock knocking against the frame if you value the paintwork.
With this method, you have to wrap it in such a way that it doesn’t interfere with your pedaling.
Suitable for:
- Cable locks
- Chain locks
- Zip tie locks
Around The Handlebar
You’d be unlikely to do this on a road bike, but on an MTB or hybrid it’s sometimes possible to wrap a lock around the handlebar. Ideally, it’s best not to do this if the lock is left dangling and in danger of snagging other bike components or unbalancing you.
Suitable for:
- On A Bike Rack / In A Pannier
Within reason, you can carry almost anything on a bike rack, so of course you can secure your lock to one as well. A big lock might be strapped on top of the rack, or you might thread it around the rack if it’s flexible.
Naturally, you can also store a lock in a pannier or cargo bag, either to the side of a rack or on top of it.
Suitable for:
- U-locks
- Chain locks
- Folding locks
- Cable locks
- Zip tie locks
In A Front Basket
If you have a front basket fitted to your handlebar, it’s perfect for carrying a small or flexible lock. You’re probably not going to carry a hefty high-security lock this way, but it’s okay for quick chores where you’re never far from the bike.
Suitable for:
- Cable locks
- Small chain locks
- Small U-locks
- Folding locks
- Zip-tie locks
Inside A Backpack
Backpacks are ideal for carrying all manner of locks, except for heavier varieties. It doesn’t make sense to bear the weight of a hefty chain lock or U-lock unnecessarily, particularly if you’re traveling any significant distance. But it’s possible.
This is a solution that may well suit many commuters, many of whom carry stuff to work daily in a backpack.
Suitable for:
- U-locks
- Chain locks
- Folding locks
- Cable locks
- Zip tie locks
In A Pocket
What could be more convenient than carrying a lock inside a jacket pocket or a deep jersey pocket? The lock needs to be compact and light to make this practical, though.
This method is ideal if you’re stopping somewhere very briefly and/or can see your bike at all times. Maybe you’re popping out to a 7-Eleven or buying snacks at a bakery during a longer bike ride.
Suitable for:
- Small chain locks
- Cable locks
- Small folding locks
- Zip tie lock
Check out our guide on locking bikes without a rack, for those who get stuck for options of not having something to lock to!
