How to stop your bike lock jamming

There’s nothing worse than a jammed bike lock. Well, there is. There’s loads of things! But when you’re struggling with a sticky key or yanking at a frozen shackle, it’s difficult to think of any.

Especially if it’s raining.

Jammed bike lock in the rain

Dave got angry and tried to force the key. It snapped

Your lock is meant to protect you. And now it’s trying to screw you. It’s like a good friend stabbing you in the back!

But the good news is: it doesn’t have to be this way! In the vast majority of cases, this problem can be avoided.

Here’s three top tips to stop your lock jamming. And at the end, some suggestions about what to do if your lock is already jammed!

3 tips to stop your bike lock jamming

Bike locks tend to jam in two places: in the mechanism so you can’t turn the key, or in the body so you can’t separate the two parts of the lock.

How can you tell where the problem is? It’s simple...

If the key won’t go in the lock or it won’t turn properly, then obviously the problem is in the mechanism.

But if the key slides in easily and turns freely but the lock still won’t open, then the problem is probably where the two parts join.

A jammed mechanism can be caused by dirt and debris, frozen water, rust or simply misaligned discs.

Whereas if the lock won’t separate, then a build up of corrosion has usually fused the shackle or bar to the inside of the lock.

Luckily for you, following three simple tips will massively reduce the likelihood that you’ll suffer from either problem…

1. Buy a good quality lock

Cheap locks are a false economy. Either your bike will be stolen because they offer such poor protection. Or your lock will start to jam because it’s not properly weatherproofed and the mechanism is rubbish.

Either way, sooner or later you’ll have to buy a new lock!

Get it right the first time instead. Invest as much as you can afford in a decent quality bike lock and it should last many years.

With this in mind, the best locks are made by Abus, Kryptonite and OnGuard. I’ve written lot’s more about the each of these brands, but if you’re looking for the very best quality, go for Abus.

Abus GRANIT Plus 640 150

Abus are an especially good choice if you live somewhere with a harsh climate. Their locks are subjected to a whole series of tests at temperatures as low as -40 degrees.

And to study their resistance to corrosion, they also use a salt air chamber which ages locks one year for every day inside. No other manufacturer tests their locks as rigorously.

You should also buy a lock with a key cover. Key covers can stop dirt and grime entering and clogging up the mechanism. But be careful, because they can also trap water which may then freeze and then jam the lock!

2. Clean and lubricate your lock regularly

High quality locks don’t need much maintenance. But a good clean and lubrication every now and then never did anyone any harm!

Make sure you clean and lubricate both the mechanism and the body where the two parts join...

How to treat the mechanism

Clean the mechanism with WD-40 [Amazon]. Turn the lock so the key hole is facing upwards and then squirt the liquid into the cylinder until it streams out. This should displace any water, dirt and debris.

WD-40 Cleaner

For locks that are really gunked up, you may need to repeat this several times. Gently inserting, turning and then removing the key between squirts will help to flush the dirt out.

Once the lock is clean, you should always lubricate it. But never use WD-40 for this.

WD-40 is a water displacing, cleaning agent and will ultimately remove any existing lubricant. It’s great for cleaning a lock. And it’s fantastic for loosening up a jammed lock. But it will not provide any long term lubrication.

Finish Line bike lock lube
Tri-Flow bike lock lube

Instead use a proper, Teflon based lubricant such as Finish Line [Amazon] or TriFlow [Amazon].

These perform well at low temperatures and repel moisture to reduce the risk of both corrosion and freezing. Put a couple of drops in the mechanism and spread it about by inserting and turning the key.

Some people recommend graphite based lubricants. These are fine for dry environments. But bike locks are invariably exposed to moisture which tends to turn the graphite into a sticky mess that collects dirt and then jams the mechanism.

Stick with WD-40 for cleaning and TriFlow or Finish Line for lubrication. Use them regularly and you'll have far fewer problems with stiff, unresponsive mechanisms and your locks will last much, much longer.

How to treat the body

You shouldn’t need to clean the lock body too much. Just give the ends of the bar and the holes in the lock a wipe with a rag now and again.

But it’s important to keep the points where the bar meets the body lubricated and free of corrosion. Especially in cold or wet climates. This will prevent the bar from starting to stick to the body.

White Lithium Grease
Where to lubricate bike lock body

White Lithium Grease [Amazon] is good for this because it’s thick, doesn’t run and will last a long time. Apply it to both the ends of the bar and the holes in the body, as and when you need to.

3. Don’t turn the key until it’s all the way in!

All locks will jam if you turn the key before it’s been fully inserted into the keyhole. Most bike lock mechanisms consist of a series of discs and all of them need to be fully rotated before the lock will open.

If you try to turn the key before it’s all the way in, it won’t catch the discs at the bottom of the cylinder, so they don’t rotate and the lock won’t open.

Once this has happened, the discs are out of alignment and you won’t be able to fully insert the key and open the lock until you re-align them.

To do this, turn the key back and forth as you gently push it down towards the bottom of the keyhole.

If this doesn’t work you can remove the key and try to tease the discs back into place with a small flat head screwdriver.

But what can I do if my lock is already jammed?

This depends on why your lock is jammed. But the first thing to do is to give it a good squirt of WD-40.

WD-40 can be a miracle cure for all sorts of jammed locks. It will displace dirt and water, remove rust and loosen the mechanism. And often this enough. However, sometimes it’s not. So…

If the mechanism is jammed...

If the key won’t go all the way in, it may be because the cylinders are out of alignment. Try the method above where you turn the key back and forth and try to gently push the key further into the keyhole as the cylinders realign.

If this doesn’t work, you might be able to re-align the cylinders with a flat head screwdriver. More WD-40 will help!

Gunked-up Key Holes

If the key goes all the way in but wont turn, then the mechanism may be jammed full of dirt and debris. Or maybe it’s started to corrode. So...

Apply some more WD-40! Insert and remove the key in-between squirts of WD-40. If it doesn’t work straight away, do it again. And again. Usually, this will work eventually.

Whatever you do, don’t loose your temper and try to force it. This is when the key will break off in the lock!

By the way, if your key does break off in the lock and you are lucky enough to own a Kryptonite lock, you can get a locksmith to remove the key, send the lock, the key, the key number and the locksmith bill to Kryptonite and they will refund the bill and send you a new lock!

Iced-up Key Holes

If you think the lock is jammed because water has frozen inside the mechanism, you’ll obviously need to melt the water before it will open...

Sometimes breathing into the keyhole will do the job. Otherwise you can try warming the key with a lighter or match and then pushing it gently into the mechanism. You may need to do this several times.

If that doesn’t work and you can bring the lock indoors, then this will obviously melt the ice eventually. But spraying the mechanism with car windscreen deicer might get faster results. I have also heard of people using anti-septic hand wash!

Whichever method you use, make sure it’s completely dry before you use it again outside, otherwise it will just re-freeze.

If the body is jammed...

If the key goes all the way in and turns smoothly, but the lock still won’t open, then corrosion has probably fused the two parts of the lock together.

In this case, try spraying loads of WD-40 into the joint. You’ll probably need to leave it some time for the WD-40 to do it’s magic. In fact, if you can, soak the lock in WD-40 overnight!

And once you’ve un-jammed your lock, don’t forget to give it a good clean and lubrication to reduce the chances of it jamming again.


A lot of the problems we have with jammed bike locks are avoidable. Buying a good quality lock, cleaning and lubricating it regularly and making sure you fully insert the key before you turn it will prevent the vast majority of problems. And you will be much happier.

Happiness is a well lubricated lock

Dave now: happiness is a well lubricated lock

However, modern bike locks are complex, precision instruments and sometimes they will just jam!

Keeping calm and being patient is important here. Lots of WD-40 [Amazon] and gentle teasing in a warm environment will usually fix the problem in the end!

Of course if it doesn’t, you’re going to probably need a new bike lock. In which case, check out the 3 simple steps that will guarantee you choose the best lock for both you and your bicycle.

But what do you think? Do you have any tips to prevent locks from jamming or to un-jam stuck locks? Let me know below…

This page contains affiliate links, which means I may earn a small commission if you click through and make a purchase. You will not pay any extra. More details here.

Click Here to Leave a Comment Below 46 comments