Bike U-locks (sometimes called D-locks or buckle locks) pretty much look the way they sound.
As far as parts and specs go, a bike U-lock is generally fairly simple. Most bike U-locks consist of a shackle, a crossbar, and a spline. In this article, I am going to share 9 best u lock a cycling enthusiastic person can buy. Rest assured, this article is thoroughly researched and that you can buy with confidence.
9 Best Bike U-Locks That Put Security First
1. Kryptonite New York Standard Heavy Duty Bicycle U Lock
If you are looking for a beast of a lock then Kryptonite New York won’t disappoint you. It is our #1 pick due to several things such as its amazing durability, anti-pick disc, protection from dust, and a security rating of 10.
Manufactured by Kryptonite, it offers all that the brand is known for.
Features: The security rating of the lock is 10 which makes it one of the most reliable options.
- Double Security (16mm hardened max-performance steel shackle + HARDENED STEEL SLEEVE over the crossbar for double security)
- A double deadbolt locking system
- Anti-pick disc cylinder
- A vinyl coating that resists scratches and rust
- Dust cover to prevent dust and external elements from deteriorating the cylinder.
The model is highly resilient against leverage attacks and lock breaking. It resists bolt cutters and lock picking. Let’s get to know about the main features of the lock:
The Perfect Size: This is a standard-sized u lock measuring 8 inches in length and 4 inches in width. Hence, it provides enough space to fasten the bike against many objects such as bike racks, rails, posts, etc.
Also, since it’s not too small, it can’t be broken easily with a bolt cutter.
Double Deadbolt Locking System: Both the ends of the shackle are locked into the shafts – not just one. Hence, the thief has to cut both the shafts to break the lock which is not easy.
Extended Life: It’s vinyl coated which makes it resistant to scratches, rust, corrosion, and other natural elements. Thus, even after years of use, the lock’s performance isn’t affected.
Anti-pick Disc: The lock system can’t be unlocked due to the anti-pick disc.
Mounting Adapter Strap: It comes with an adapter strap to mount the lock when not in use.
What to like about the product
The combination of 16mm shackle, deadbolt design, vinyl coating and steel sleeve over crossbar gives it a durability that no other lock gives.
The lock can’t be picked easily and is meant to last for years as the dust cover gives protection against dust and vinyl coating protects against other natural elements.
It’s difficult to find a lock with so many features in this price range.
What not to like about the product
The adapter strap moves a lot and hits on the legs. The solution is to fasten it with a tape.
Pros
- Superior durability.
- The keyway is in the center which makes it difficult to do leverage attacks.
- Lifetime limited warranty.
- Weather resistant.
- Comes with 3 keys and master key with an LED feature.
Cons
- Little heavy at over 4 pounds.
- A bit small in size.
- A bit expensive.
2. Kryptonite New York LS Heavy Duty Bicycle U Lock
The runner up on our list is yet another Kryptonite lock because it provides the same endurance than our first pick does but with a few minor changes including a security rating of 9 and slightly changed dimensions.
Features: Offers superior resistance against bolt cutters and cutting tools.
- A 16mm hardened max-performance steel shackle and a steel sleeve over the crossbar for additional protection.
- A locking system that depends on both shafts.
- Unpickable disc cylinder.
- PVC coating doesn’t scratch the bike’s paint or give scratches to the lock.
- Sliding dust cover prevents dust and natural elements from damaging the keyway.
It offers the same resiliency as our first pick since it is made up of the same materials. It’s slightly bigger and comes with an anti-theft protection.
Some of the main features of the lock are:
Good Size: It measures 10.2 inches in length and 4 inches in width. The extra length helps to lock both smaller framed and larger framed bikes easily.
Double Deadbolt Locking System: The lock works on a double lock system so damaging one shaft won’t make the lock useless.
Dust Cover: The sliding dust cover helps keep the keyway dust and rust free. Thus, the lock works for years to come.
Anti-Pick Disc Cylinder: The lock system can’t be picked with any tool but can only be opened with a key.
Mounting Adapter Strap: It comes with an EZ mount transportation adapter strap to mount the lock when riding the bike.
What to like about the product
Provides protection in many ways. 12mm steel shackle, PVC coating, and a secure locking mechanism make it nearly impossible to tamper with the lock. Moreover, the company offers an anti-theft program that pays for your bike, if it is lost. However, you must register on the website first.
What not to like about the product
The mount bracket is quite heavy and causes a bit of a trouble when riding the bike because it is not completely fixed to the frame.
Pros
- Enhanced protection.
- Longer in length.
- Difficult to pick and break the lock.
- Lifetime limited warranty
- Weather resistant.
- Comes with 3 keys and a master key with an LED feature.
- Key safe program (company sends extra keys in case original ones are lost).
Cons
- Heavy with over 4.4 pounds.
- A bit expensive.
3. ABUS Granit X Plus 540
Just like the previous two locks, this one too has a gold rating, making it one of the best in security testings. The lock is manufactured by ABUS, a company that makes highly durable locks. For the complete review of granit 540 model, you can check out this article here.
It has slightly pointed ends to make it difficult to pry, pull or break the shackle. Moreover, it is long enough to even lock two bike frames together.
Features: Long and stiff shackles to resist serious attacks
- ABUS security rating 15/15
- 13mm German steel made shackle that is hard to tamper.
- Power Cell locking system.
- Double bolted lock.
- Protective covering over the shackle.
If you are looking for a U type lock that can provide you with peace of mind when you park and lock it then this U lock is an excellent choice.
It may be a bit pricey but is worth it!
Power Cell Lock System: The shackle makes use of the patented Power Cell locking system that can withstand 17 tons of pulling abuse.
Double Bolted: The shackle is double bolted as well. No thief will be able to break it quickly even when using the sharpest of tools as both the shafts need to be broken.
Size: Being 11.6 inches long and 7 inches wide, this lock can bind two bikes at once, and is suitable for large framed bikes as well.
Pick Protection: The lock isn’t easy to pick with any picking tools as the internal construction of the disc has pick protection.
What to like about the product
Quite long and wide in size and is also made up of tremendous build quality that can’t be easily jacked up.
It can resist an immense amount of pulling force.
What not to like about the product
No mount bracket included even with such a price tag.
Read our full review of the Abus Granit X Plus 540 bike lock.
Pros
- Pull and break resistant to conventional tools.
- Comes with 2 keys (1 LED key).
- Keys can be replaced if lost.
- Stylish lock with a curvy shackle.
- Less heavy compared to locks in the same price range.
Cons
- No mount bracket.
- Plastic disc but there’s a steel plate inside.
- A bit expensive.
4. Sigtuna Gear [ Best Budget ]
This u lock offers security and convenience by offering a hard to break 16mm
shackle and one button release mounting bracket along with a 1200mm double looped flex cable to add more security to your bike.
Features: Double security in the price of one (U lock + flex cable.)
- Works with foldable bikes, too.
- Mounting bracket to hold the lock.
- Double bolt lock resists pulling, prying and breaking.
- Security rating 8/10.
- Pick proof.
It’s a tested U lock and surprisingly withstood some of the heaviest blow and cutting tools.
Sturdy Mount Bracket: The mounting bracket has rubber fittings to attach firmly to the bike. It works on a one-button lock release mechanism so that you can attach and detach the lock in a second. Also, the bracket can be fitted on multiple places without any trouble.
Protective Vinyl Coating: The problem with cables is that they scratch off the paint but not this one as it is coated with a protective vinyl coating.
Anti-Theft Design: This lock offers an anti-theft design due to the combination of a double lock system that won’t break even if one side of the lock is penetrated. Plus, the disc cylinder is also very hard to pick.
Key Hole Cover: There’s a cover on the keyhole to prevent dust, particles and
outside elements from damaging the keyhole and shortening the lock’s life.
What to like about the product
You can lock large framed bikes and even foldable bikes thanks to the flex cable that comes with it.
The lock itself is big with 9.4 inches in length and 7 inches in width.
What not to like about the product
The mounting bracket won’t fit on thin tubes and keeps on making movements which can be frustrating. Read the entire Sigtuna Gear Review here.
Pros
- Easy to use and attach to the bike.
- Resistant to leverage attacks and cutting.
- Comes with a one button release mounting bracket.
- Full refund policy if the lock doesn’t provide quality (conditions apply).
- Doesn’t damage bike paint.
Cons
- The lock doesn’t fit tight enough on the bracket and fits even poorly on a bike with thin tubes.
5. Amazer Heavy Duty Combination [ Best Budget ]
This one is a keyless and password protected U lock that will free you from keeping a track of the keys.
The lock is highly durable and offers great ease of use.
Features: A keyless lock with heavy duty protection.
- Superior durability (12mm hardened performance steel shackle + 3.85mm PVC coating).
- 4 digit key combination lock
- Lightweight – 1.8 pounds.
- Zinc alloy cylinder.
- A dust cover to protect the lock’s life.
There are many amazing features of this lock. It is quite reliable and comes with a zinc coating. Plus it is affordable as well.
Total Thickness: It is meant to go a long way because of the total thickness it has (12mm shackle+3.85 PVC coating). The dimensions are quite good as well (28.6 inches in length, 5.74 inches in width) and a 28.6mm thick crossbar. Hence, it takes a lot of effort to break the lock.
Hard To Predict Password: It’s a password protected lock (4 digit code) which offers great security.
Easy To Use: The default password is 0000, which can be changed by pressing the reset switch at the left of the crossbar. The shackle doesn’t leave the crossbar until the correct password is entered.
Dust Cover: The dust cover protects the numeric combination. It keeps dust and particles at bay, extending the lock’s life.
Safety For Bike Paint: The PVC coat on the lock doesn’t scratch off the bike’s paint.
What to like about the product
The keyless feature saves time and makes it easy to exchange bikes as you only have to share the password and not the key.
What not to like about the product
No mounting bracket makes it a hassle as you’ve to carry the lock when riding the bike.
Pros
- 30 days money back guarantee in case there’s a defect.
- No keys required to unlock.
- Affordable.
- Doesn’t damage bike paint.
- Easily carryable as it’s 1.8 pounds.
Cons
- No mounting bracket.
6. Kryptonite Kryptolok Series 2 Mini-7
If you live in a lower risk area then this moderate security U lock can be of help. Kryptonite has given it a security rating of 6 out of 10 as it is not made for high risk regions.
Features:
- 13 mm steel shackle and 4 feet long cable
- Lightweight – 2.8 pounds.
- Safe key program (duplicate keys available).
- A rotatable dust cover to prevent weather elements.
What to like about the product
Much better than most u locks in the price range. It offers moderate safety for your bike.
What not to like about the product
Extremely poor mounting bracket quality. It doesn’t hold the lock firmly and can break as well if too much force is applied.
The endurance isn’t up to the mark. The lock can be broken with a heavy bolt cutter or by drilling into the side. It’s only good for low safety areas or to provide you with mental security as locks can deter thieves even if they aren’t very effective.
Pros
- Comes with two keys and a key safe program as well.
- Affordable.
- Doesn’t damage bike paint.
- The covering on the lock doesn’t scratch paint.
Cons
- Poor mounting bracket.
- Breaks easily due to less thickness and no double bolt system.
- Cable isn’t much durable.
We have done some analysis and published an article on Kryptonite Evolution Mini 7 Review here. We went ahead and stated what we liked and did not like. Give it a shot and let us know what you think.
7. Abus Mini Round Shackle [ Suitable For Mountain Bikes ]
Features:
One thing I like about this product: maximum security at a fraction of the weight.
- Lightweight
- Compact design
- Premium cylinder protection
- Corrosion-resistant
- Double bolting mechanism
Product Highlights
What makes this Abus lock a great choice for mountain bike owners is that this particular U-lock can keep your bike secure while still being compact and lightweight. This is an important aspect for mountain bike owners since a lot of them generally travel a lot & they need something portable.
What I like
The Abus brand pays attention to security. Their long years of developing technology have given cyclists top-notch premium cylinder protection, double bolting shackle, and German-engineered 14mm hardened steel with the ability to withstand bolt cutters and other types of manipulation.
What I don’t like
The design is compact, and relatively lightweight for its material, but the size can make it difficult for certain types of mountain bikes to lock at points of attachment such as bike racks. If you have a mountain bike with a bigger frame, consider buying a bigger U-lock.
Pros
- Lightweight
- Maximum security
- Portable
- Double shackle
- Cylinder protection
Cons
- Does not have a frame mount
- May not be useful for bigger bikes
8. Kryptonite Evolution Series 4 Standard Heavy Duty Bicycle U-Lock [ For Mountain Bikes ]
Features:
One positive thing about this product: innovative design to keep your bike safe
- Hardened oval crossbar
- Double deadbolt design
- Sliding dust cover
- Disc-style cylinder
- New transit flexframe-U
Product Highlights
All of the Kryptonite’s unique security designs combined make this an ideal option for cyclists who live in moderate to high crime areas.
The bar of this, U-lock as well as its interior, make it resistant against bolt cutters, leverage attacks, and twist attacks.
If you own a mountain bike and wish to protect it in high-risk areas, consider the Kryptonite series U-lock.
What I like
This product is heavier than other items we have mentioned, but it is a solid lock that can withstand multiple forms of attack.
Aside from the security that this U-lock offers, it can also give you peace of mind with their key replacement program and anti-theft program.
Moreover, mounting with this lock is very easy compared to other U-locks, allowing you to lock your mountain bike easily to multiple points of attachment.
What I don’t like
As mentioned before, this U-lock is heavy which means it will be more difficult to carry around while commuting or traveling. Nevertheless, it is still portable despite its size and weight.
Pros
- Solid security
- Anti-theft program
- Key replacement program
- Very strong steel
- Maximum protection
Cons
- Slightly heavy
- Less portable
9. ONGUARD Double-Team PITBULL U-Lock and Cable [ For Mountain Bikes ]
Features:
One positive thing about this product: dual protection for all types of bikes.
- U-lock with a double-coated, braided steel cable
- X4P locking mechanism
- Lighter than other variants
- For bikes and Powersports
Product Highlights
The ONGUARD is unique in its dual protection that features a U-lock in combination with a chain lock. For cyclists who need both locks, this product offers the best value while also providing security and strength.
What I like
This product offers dual protection with a U-lock and a cable lock combined, with both locks being crafted from strong materials. The ONGUARD U-lock and cable combo can protect your bike in high-risk areas with many cases of prying, cutting, and jacking, while also allowing you to mount your bike easily to bike racks or posts.
What I don’t like
Even though this product can protect your mountain bike well, it can be a less than ideal option for cyclists who commute very often or use their bike recreationally. Due to the ONGUARD’s weight, it’s not easy to carry for everyone. Moreover, the whole lock is relatively big and is not easy to store or mount while riding.
Pros
- Dual protection
- Bike protection offer
- Powersports offer
- Superior protection
- Includes five laser-cut keys
Cons
- Too big for some cyclists
- Not very portable
Factors To Consider When Picking A U Lock
To pick the best U lock on the market one must consider the following factors:
Double Deadbolt Design: Choose a U lock that has a double bolt design. It’s a design where both the ends of the shackle are deeply locked inside the disc cylinder. The benefit is that even if a thief succeeds at breaking the lock from one end, the lock won’t come apart and will stay locked until the other end is broken as well.
Thick Steel Shackle: Don’t settle for a U lock that has less than 15mm thickness. The thickness of a shackle is the most important part of a lock. It is hard to pull, pry or break and will withstand the sharpest and strongest of bolt cutters.
On the other hand, locks with poor shackle thickness come apart easily.
Weather Resistant: Weather can be harsh in some areas. It can rain heavily or receive dust storms too often. Here’s where it can sustain rust or get damaged.
The real problem occurs with the keyhole as it accumulates debris and dust easily which can jam the lock and even scratch it from the inside, making it hard to unlock.
Therefore, it is important to choose a U lock that has a PVC coating on it to prevent scratches and rust. Also, a dust cover on the keyhole is quite handy as it can protect the key passage from outside elements.
Mounting Bracket: A lock without a mounting bracket can be troublesome. Mounting bracket eliminates the hassle of having to carry. So opt for one that comes with a sturdy and easy-to-install bracket.
Price: Your budget should decide which U type lock to go for. It’s not a wise choice to pick a $200 lock to protect a $200 bike. However, one shouldn’t compromise on the price factor if you own an expensive bike.
Warranty: Consider going for a lock that comes with a warranty. Some may even pay for the bike in case of a theft.
Tips:
- Park your bike in a public place.
- Don’t park in a dark place.
- Attach the lock in a way that it locks the wheel and the frame together.
- Install a GPS tracker on the bike, if possible.
- Make sure the pole or object you are locking your bike against is hard to tamper with.
Final Words
Our top pick when it comes to a bike U lock is Kryptonite New York Standard Heavy Duty because it has a strong and thick shackle that resists bolt cutters and other cutting tools.
It comes with a durable and smooth mounting bracket and has a double bolt lock design. Not to forget that it has a 10/10 security rating as well.
Don’t Forget : There are different categories of lock available in the market today. We have already done the hard work and put together couple of mega guides for it.
