How To Break A Kryptonite Lock For A Bike

So you have lost the key to your Kryptonite bike lock? Don’t worry. We will assist you in searching for it, but if it is still missing after the search, there are a few proven ways to break the Kryptonite lock for the bike. Obviously, without a key, the only option remaining is to pick the lock or break it.

Are There Ways To Break A Kryptonite Lock For A Bike?

A Kryptonite U-Lock might be hard to defeat, but it can be defeated just like any other lock when the situation demands. There are several methods of breaking the lock. The simplest and safest method of them all is trying to jimmy the lock using a ballpoint pen. However, other methods will compel you to use force that will eventually damage the lock and reduce it to an unusable state.

Ways To Break A Kryptonite Lock For Bike 

The methods that can be employed to defeat the lock include;

1. Jimmying it Using a Ballpoint Pen.

2. Breaking it Using the Hammer.

3. Cutting it Using Angle Grinder.

4. Using a shim to Open the Lock.

Here below, each method is discussed on a case-by-case basis.

1. Jimmying The Lock With A Ballpoint Pen

Jimmying is the simplest and easiest method to employ if you desire to use the bike lock again. You are picking the lock and not opening it the usual way and it involves finding a standard ballpoint pen with a popping-off end instead of the one that screws off. 

 Remove the cap using your fingernails. and remain with a hollow tube with the same diameter as a standard Kryptonite keyhole. Next, insert the tube into the lock’s keyhole lock and ensure it fits within the hole. Suppose the tube doesn’t fit well, search for a fitting one. Non-fitting tube can’t perform the task.

Now that you have a fitting ballpoint tube push it into the keyhole and twist it inside the Kryptonite lock while pulling the lock. Keep twisting while shaking the bar of the lock, applying pressure. Be patient with your twisting until you hear the locking mechanism unlocking.

Check to ensure your lock is open, but if you are still applying pressure, you will feel the moment the lock opens.

Now that your Kryptonite lock is open pull the ballpoint pen out of the lock, and there you are with your lock open.

2. Breaking The Lock With A Hammer 

If you want to open the Kryptonite Lock using a hammer successfully, you should use a canned air spray to weaken the lock before forcing it open.

How does the canned air spray weaken the lock? The air spray consists of a compressed chemical known as difluoroethane. The chemical cools the lock to -13 degrees Fahrenheit, making it weaker. 

Position the lock so that the bar of the lock is supported by the bicycle rack’s bar. At this point, spray the canned air into the keyhole of your lock. Use the trigger supplied with the canned air to ensure penetration and spray the solution directly into the keyhole. Continue spraying until you notice the bar reaction with the Kryptonite’s surface. Be sure that the spray is aimed at the keyhole’s radius because this is the spot where your hammering will be centered.

Now that your U-Lock is weakened aim your hammer at the keyhole and keep hammering patiently until the U-Lock breaks.

3. Cutting The Lock Using An Angle Grinder

An angle grinder is a sure way of breaking the Kryptonite and other types of locks. However, the process is hazardous; hence you will require protective gear before commencing the dismantling process.

Before attacking your lock with the grinder, ensure that you are comfortable with its operations. The protective gear required to operate the angle grinder is gloves and goggles. 

Gloves will protect your hands, while goggles will protect your eyes from materials frying away from the lock.

Precaution When Grinding The lock

1. Ensure you are using the correct size of disc for grinding.

2. Ensure that the grinder runs at a maximum speed.

3. Avoid wearing loose clothing or jewelry while operating the angle grinder.

To use the angle grinder, adjust the lock until you are satisfied that it does not move when pressure is applied but stays in the same position. 

When cutting the lock, use both hands to steady the grinder, and slowly start cutting one side of the U-lock until the blade cuts through. Ensure that you cut both deadbolts before switching off the angle grinder and removing the lock.

While cutting the lock, be patient and deliberate with your angle grinder. Avoid exerting pressure since this might end up cutting through and damaging your bike. 

Be Warned

1. When using an angle grinder to break the Kryptonite lock, be careful and ensure you adhere to safety precautions.

2. If it is your first time using the grinder, ensure that you have familiarized yourself with it before embarking on lock cutting.

3. Ensure the lock you are breaking is yours. Don’t attempt breaking someone’s lock with the intent of stealing the bike.

4. Use A Shim

You can design a shim and try your luck in opening the lock. A shim is usually made from bubbling drinking cans, and it works by inserting it against the interior of a shackle, then slide it towards the locking latch. Hold it firm and pull the shackle up when you are sure the shim is in the correct position. Suppose your lock uses two deadbolts; you will require two shins to accomplish the task.

However, the shim might not work on expensive locks since they have complex features that defend them from ordinary picking devices. Although with a bit of luck, this method might work out.


If you are stranded because you have lost the key to your bike’s lock, calm down and follow the above-given steps. However, opening the lock using the key is the best option; thus, search for it if necessary.

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