U-locks (aka D-locks) are a bit like giant padlocks that fasten around your bike and whatever you're trying to secure it to.
First developed in the 1970's by the company that would go on to become Kryptonite, u-locks revolutionized bike security by providing similar protection to chains at a fraction of the weight and cost.
If you’re only going to buy one bike lock (and maybe you should buy two), then a u-lock is usually the way to go. Why?
Well, I think they offer the best balance between security, practicality and price!
If you're not sure about this, check out my complete guide to the best bike locks where I compare u-locks to chains, cables and folding locks in much more detail.
But if you're already convinced, how can you know which u-lock is best? There’s a bewildering range of sizes, weights and prices from a slew of different brands.
The truth is: there isn't a definitive "best u-lock". The best lock for one person may be totally unsuitable for another. So you need to think about your specific needs and work through it from there.
Don't worry! It's actually pretty straightforward. And this guide will take you through a simple step by step process to make sure you choose the best u-lock for your individual circumstances.
And then at the end, I recommend a few of my favorite u-locks according to the different security levels and sizes available...
How to choose the best u-lock for you
The best u-lock for you will fulfill two vital requirements. It will obviously be secure enough to stop your bike from being stolen! But it will also be practical to use on a daily basis.
This second requirement is often overlooked. But whichever u-lock you choose must be both easy to carry around and must also fit easily around your bike and whatever you want to lock it to.
This issue of practicality is most determined by how big a u-lock is, so we can divide the process of choosing the right u-lock into three simple steps...
Firstly, decide what security level you need. Secondly, choose the appropriate size of u-lock. And then thirdly, find a specific lock within your budget.
Step 1: Choose the right level of security
The easiest way to determine the security level you'll need is to answer the 3 questions in the table below...
Where do you live?
Big town, city or university campus
Small town or village
Does your bike attract second looks?
How long do you leave your bike unattended?
More than 1 hour
Less than 1 hour
If two or more of your answers are in the “High Risk” column, then you’ll need a lock that offers a higher level of protection.
If two or more of your answers are in the “Lower Risk” column, then you can probably get away with a lower security lock.
How do I know how secure a u-lock is?
The easiest way to judge how secure any bike lock is, is to look at the ratings from the testing organisations Sold Secure and ART. Both of these groups test and then rate a huge number of locks according to their security level.
Sold Secure use a Bronze, Silver and Gold rating system (with Gold clearly the most secure). While ART use a star system with locks rated between 1 and 5 stars (5 stars being the most secure).
ART seem to be more demanding than Sold Secure. For example most Silver locks only get 2 stars from ART. But I prefer to use Sold Secure as they test more locks.
So, if you're "Lower Risk" from the table above you should go for a lock that's rated at least Sold Secure Silver.
And if you're "High Risk", go for a Sold Secure Gold rated lock. I don't recommend any locks that are rated Sold Secure Bronze as I don't think they offer enough protection for any circumstances.
Extra Security Considerations
So you know you'll need either a Silver or a Gold rated lock. But these ratings are quite broad; there can be big variations in the actual levels of security offered by different locks in the same Sold Secure rating.
What I'm saying is: some Silver rated locks are more secure than other Silver rated locks! And likewise for Gold rated locks.
And if we know which features cause this variation, we'll be better able to distinguish one lock's real level of protection from another. So let's go over them...
This is probably the biggest determiner of how strong a u-lock is. Usually, the thicker the shackle, the stronger the lock. However, the type of metal is important too so they should always be made of hardened steel.
U-locks with diameters of less than 13 mm could be susceptible to attacks by medium sized bolt cutters which some opportunist thieves do use.
Better u-locks, with diameters of between 13 and 15 mm are unlikely to be defeated by anything but the biggest bolt cutters which most casual bike thieves just won’t have.
However some thieves will, so at the top of the range there are the thickest locks, with diameters of 16 to 18 mm which cannot be cropped by even the biggest bolt cutters.
Can be cut by bolt cutters?
< 13 mm
Yes (medium size)
13 - 15 mm
Yes (only biggest 36 and 42")
16 mm and above
Of course even the thickest u-locks can be defeated by power tools such as angle grinders. But there is not a huge amount we can do about that.
All we can do is buy the strongest lock we can afford (such as the extremely "angle grinder resistant" Litelok X1 or Hiplok D1000), and try to limit the opportunities any thief will have to work on it with power tools!
So in terms of security: the thicker the shackle the better!
Shackle Locking: Single or Double?
On less secure locks the shackle only locks into the crossbar on one side. This means that it only needs to be cut once (on either side) before the shackle can be removed with a simple twist.
Whereas if the shackle locks into the crossbar on both sides, it needs to be cut twice (once on each side) before the lock can be defeated.
Locks that only lock on one side are also much more susceptible to leverage attacks. And since this is the most common form of attack with u-locks that have shackle diameters greater than 13 mm, it's really important!
In leverage attacks a length of metal (often a piece of scaffolding pole or a long crowbar) is inserted into the space within the u-lock and then twisted usually using the thief's weight for maximum force...
With locks that only lock on one side, eventually the other side of the shackle will pop out under a leverage attack. Locks with double locking shackles can also be defeated with leverage, it's just more difficult.
So remember: double locking shackles are more secure than single locking shackles!
That Extra Cable Lock!
Many u-locks, (including several of the locks on this page) come with an extra length of braided cable with a hoop at each end.
They can be used in conjunction with the u-lock so that while the lock secures the frame and one wheel, the cable secures the other wheel.
The cable is very light (and cheap). So you can secure the most valuable parts of your bike without adding too much weight (or cost) to your u-lock.
In reality these cable locks offer very little practical protection. A thief with a small pair of hand held wire cutters can snip through the cable as easily as scissors cut through a piece of string. And all bike thieves carry such a tool.
So they only protect you from the most casual of thieves. I certainly wouldn't depend on them to protect valuable wheels with quick release levers anyway.
Whats more, these cables are not so easy to gather up and carry around. You have to coil them up and then tuck them into a bag or around the u-lock. I find them a real pain. I talk about better options below.
Internal Locking Space
In the first video above, the thief had to insert a metal pole into the space within the u-lock before he could start his attack.
And it's not just poles and leverage attacks that work this way. Hydraulic bottle jacks must also be inserted into the space inside a lock in order to break it open...
But the point is: if they can't fit their tools inside the lock, they won't be able to defeat it with these methods.
And this is where the internal dimensions of a u-lock are important. The less space there is, the less room there is for foreign tools that can be used to force the lock open.
So smaller locks are more secure right? Well, sort of. Smaller locks do have less internal space. But you can still leave plenty of room for an attack tool if you fasten a mini lock around your top tube.
And if you fasten a larger lock around your frame, a wheel and a pedal you can make sure that there's no spare room!
So it's actually more about locking technique than the inherent security levels of different sized locks. But you should be aware of this factor when you decide which size of lock you need and how you'll use it...
Step 2: Choose the right size u-lock
There are number of factors that will determine which size u-lock you should go for including whether it's a primary or secondary lock, how you'll carry it around, what type of bike you ride and where you usually leave it.
Is it a primary or secondary lock?
A primary lock is responsible for making sure your frame's not stolen. So it normally needs to be big enough to go around your frame, one wheel and whatever you're locking your bike to.
A secondary lock is only responsible for making sure the other wheel isn't stolen. Since it only needs to go around either one wheel and the immovable object or one wheel and the frame, it can be significantly smaller.
So, if you use both a primary and secondary lock you're protecting your frame and both wheels.
But do you really need two locks? Well, not necessarily. Wheels that are attached to your bike with quick release levers or regular nuts are very easy to steal. And I'd recommend that you'd take some measures to prevent that...
Normally that would be a secondary lock. But there are other options (one of which is the cable lasso I mention above).
None of the alternatives will be as secure as secondary lock but they may be sufficient. And if you only need to carry one lock, you'll be saving a lot of weight!
What type of bike will it secure?
Different types of bike have different size frames and tires. And this will affect which size u-lock is appropriate for you.
So if you ride a fat tire bike, an electric bike or even a mountain bike, you'll have wider frame tubes and thicker tires. There's also likely to be a bigger gap between the wheel and the frame. All this means you'll need a longer, wider u-lock to fit everything inside it.
Whereas if you ride a road bike, a city bike or even a hybrid you'll have thinner frame tubes that have less space between much thinner tires. So you'll be able to get away with a much smaller u-lock.
It's a good idea to measure the distance around your frame and wheels to make sure that you'll get a u-lock that fits. And don't forget it needs to go around an immovable object as well!
How will you carry your u-lock?
How you'll carry your u-lock is to a large extent determined by the size and weight of the lock and the quality of the frame mount that usually comes with it.
The frame mount is normally a plastic bracket that fixes to the frame of your bike, into which the lock clips while you are riding around.
Depending on which type of bike you have (and what other accessories are attached to your frame), the mount can usually be fixed in a number of different places including the top tube, the seat tube, the down tube or even the seat stays or handlebars.
Unfortunately, it's difficult to design a universal frame mount that will fit every bike and hence many cyclists complain about their performance, especially those that come with the cheaper locks.
A good frame mount should fix securely to your frame and hold the lock tightly so it doesn’t move about while you are riding.
However, there are many reports of mounts that are difficult to attach to the bike, not tight against the frame and unable to prevent the lock rattling about or even falling off when the bike is being ridden!
Of course you don’t have to use the frame mount that comes with your lock. You could carry it in a bag. However, bear in mind that locks get wet and dirty and some U-locks are heavy enough to make carrying them on your back very uncomfortable.
You could also put it in your basket or clip it to your luggage rack if you have one. You can even fit the smaller ones in your pocket! The Hiplok (see below) comes with clip that will attach it to your belt or bag.
And because many of the normal mounts are so poor, there are also lots of third party solutions. Holsters that go round your waist. Brackets that attach to your handlebars.
Or invent your own method! I just thread the shackle of my U-lock through my seat rails and then lock it up in between the seat stay and the seat tube.
What’s important, is that you think about how you’re going to carry it before you buy your lock.
Bigger u-locks are more difficult to carry in bags and impossible to tuck into pockets and hang from belt loops. So you're pretty much limited to the frame mounts, luggage racks or panniers.
They tend to fare worse in frame mounts too. This is because their center of gravity is further from the frame, so they're more likely to move around and work loose.
Smaller locks will obviously be easier to carry, whether on a frame mount, in a bag, slipped into a pocket or hanging from a belt. But of course they give you less locking options!
Be aware that some u-locks (usually the smallest and the biggest) don't come with frame mounts. Make sure you check before you buy.
Where will you lock your bike?
Think about where you'll normally lock your bike. Will you use public bike racks? Or will you use lampposts? Or railings? How wide and deep are these objects?
Different types of immovable object demand different size u-locks. Public bike racks are usually much thinner than lampposts for instance. But some bike racks are thicker than others.
It's no good buying a nice mini u-lock if you routinely need to lock your bike to a street sign or a lamppost. It simply won't fit!
Standard vs Mini Sized U-Locks
We can divide most u-locks into two broad groups based on their size. Standard size u-locks are around 9" tall and 4" wide (23 x 10 cm). While Mini u-locks are around 6" tall and 3.5" wide (15 x 9 cm).
Standard size u-locks are great because they give us loads of locking options. Bike racks, street signs, traffic lights and railings are all usually accessible with a standard sized u-lock.
And whether the place you choose is empty or busy with other bikes, the generous dimensions usually make it easy to find an angle that will allow you to successfully lock your bike.
Plus if you want to lock one wheel and the frame on certain bikes (mountain, fat tire, city comfort, electric etc) you'll probably need a standard size u-lock anyway.
The disadvantage of standard size u-locks is that being bigger, they're also heavier and bulkier which makes them more difficult to carry (especially the higher security ones). Which is where mini u-locks come in...
Mini u-locks are smaller and lighter. So they're easy to slip into a bag, thread through a belt loop, shove in a back pocket or just hang from your handlebars.
Carrying a mini u-lock is much less hassle than a standard size. And even if you use a frame mount, you're less likely to encounter problems, as the reduced weight and a center of gravity closer to the frame mean they tend to remain more firmly and quietly held in place.
Also as I mention above, mini u-locks have less internal space which makes them potentially less susceptible to some of the most common forms of attack. However as I also mention above, this can be as much to do with locking technique as the locks themselves.
The disadvantage of mini u-locks is that they give you far fewer locking options. On many bikes, they won't fit around the down tube and the tire, so you'll need to fasten them round the seat stay and through the spokes.
This is slightly less secure in theory (but probably wont make any difference in practice)!
And in most places you can forget about lampposts, street signs and traffic lights. A mini u-lock just won't fit around these things. So you're pretty much limited to bike racks.
With the limitations of mini u-locks in mind, there is a growing trend for medium size u-locks. In theory a medium lock would sit somewhere in between standard and mini sized.
But in fact, they are usually just longer mini u-locks! This means they are the same width as mini u-locks, which is much narrower than standard locks.
This is important because it means that anything wider than a bike rack is still off-limits. So no lampposts, street signs or traffic lights with most medium u-locks either.
However you will get better angles in the bike rack. So locking your bike will be easier and you maybe able to get the lock around your tire and your down tube where other wise you wouldn't.
Beyond medium locks, there is great deal of variation in sizes, especially between the different brands. And there are wider or taller variations of the same models as well. So you should be able to find one that meets your requirements exactly...
Step 3: Choose the right u-lock for your budget
So you know what security rating you need and how to judge the different levels of protection within that rating.
Hopefully you know the u-lock size that will suit your type of bike, the places you'll lock it, the way you'll carry the lock and how you want to use it.
Now it's time to choose a specific lock that matches those requirements. You could take a look at the u-locks in my extensive lists of Sold Secure Gold and Silver bike locks. Or you could browse this exhaustive list of every u-lock I could find.
On all three pages you can compare the weights, lengths and widths of the locks to find one that meets your needs exactly. And if you click through you can compare the different prices.
How much should I spend?
There are huge variations in the price of u-locks. And the price doesn't always relate directly to the level of security they provide. Indeed, there are plenty of very cheap, high security u-locks!
But be careful: one of the biggest problems that we have with all bike locks is reliability. There are so many complaints and queries about jammed, impossible to open bike locks that I had to write an article about it...
Cheap bike locks are generally made with poor quality components that will not stand up up to prolonged exposure to outside weather conditions. They will corrode and then they'll stick and you won't be able to open your lock.
It's much better to spend a little more than you'd like to on a decent quality lock than to buy a budget lock that stops working in a year or so, causing unknown stress and forcing you to buy another one. It's also the greener option!
Of course, not everyone can stretch their budget so if you're forced to buy a cheaper lock then make sure you clean and lubricate both the mechanism and the ends of the shackle frequently. More details about how to avoid and fix jammed bike locks here.
But if you keep reading, I recommend my three favorite u-locks for a variety of different budgets in each security and size category ...
The 3 Best High Security Standard Size U-Locks
The only way these three locks can be defeated is with power tools. And you'll never to struggle to find a place to lock your bike if you're using one of them. In no specific order...
Kryptonite New York Standard
16 mm shackle
4.35 lb (1.97 kg)
4" (10.2 cm) wide
8" (20.3 cm) high
16.8 mm shackle
4.67 lb (2.12 kg)
4.4" (11.1 cm) wide
8" (20.3 cm) high
Abus Granit X Plus 540 Standard
13 mm shackle
3.2 lb (1.45 kg)
4.3" (10.8 cm) wide
9" (23 cm) high
1. Kryptonite New York Standard
This is Kryptonite's most secure, standard sized bicycle u-lock and it boasts a 16 mm shackle with double deadbolt locking (which means it locks on both sides).
It’s slightly narrower than its rivals, which makes it more secure, but also means you'll have slightly fewer locking options. It’s also the heaviest of the three recommended locks.
But this is clearly the most secure lock of the three and it's the only one with a very impressive 4 star security rating from ART.
And like all Kryptonite's locks, it benefits from great after sales care, which in this case includes optional anti-theft protection up to $3000 / £1200.
If this one's a little heavy, then check out the Kryptonite Evolution Standard. The shackle is 14 mm which means it's significantly lighter. But it still gets a Gold rating from Sold Secure and 3 stars from ART.
But, if you’re looking for the ultimate in protection without sacrificing the number of the places you can lock your bike, the New York Standard [Amazon] could well be the best U-lock for you.
2. OnGuard Brute Standard
OnGuard's most secure, standard sized U-lock also boasts a 16 mm shackle but ramps up the locking mechanism to give you quadruple deadbolt locking! However, whether this makes it any more secure is highly debatable.
The real advantage the Brute has over its rivals is in the price. At around half the price of the New York standard and much less than half the price of the Granit X-Plus 540, it’s an absolute bargain!
Again, if this one seems a little heavy then there's a lighter version, the OnGuard Pitbull Standard [Amazon] which has a narrower 14 mm shackle but retains the Sold Secure Gold rating.
Yes, the after sales service may not be as good as Kryptonite. And OnGuard locks usually need a little more care and attention with regular cleaning an lubrication.
But if you’re looking for the ultimate in practical protection at a budget price, the Brute Standard [Amazon] may be the best U-lock for you.
3. Abus Granit X Plus 540
The Abus Granit X Plus 540 is a bit of an anomaly. The shackle is only 13 mm thick, but because of the special steel they use and the triangular shape, it’s effective strength is equivalent to much thicker shackles. It's also double bolted of course.
This means that the lock can be lighter without sacrificing security! It's not quite as secure as the New York Standard, but it's significantly lighter than both it's rivals despite being slightly bigger.
OK, it’s also much more expensive than it’s rivals. But you get fantastic build quality with all Abus locks which means they're less likely to jam or stick as they age unlike cheaper locks.
This is my favorite u-lock and I think it's a fantastic, high security all rounder. It's size gives you loads of locking options. It's a reasonable weight. And it comes with a dependable frame mount that makes it easy to carry.
Plus the high build quality means it's unlikely to let you down in adverse weather conditions or seize up as it gets older.
So if you’re looking for the lightest u-lock without sacrificing either practicality or security, maybe the Granit X Plus 540 is the best u-lock for you.
You can read my full review of the Granit X Plus 540 here. Or you can also read how it compares to the best lightweight bike locks.
The 3 Best High Security Medium U-Locks
These three locks are easier to manage than the standard size u-locks while still offering loads of options in the bike rack. In no specific order...
14 mm shackle
3.32 lb (1.51 kg)
3.55" (9 cm) wide
6.9" (17.5 cm) high
13 mm shackle
3.55 lb (1.61 kg)
3.25" (8.3 cm) wide
7" (17.8 cm) high
17 mm shackle
2.36 lb (1.07 kg)
3.35" (8.5 cm) wide
7.1" (18 cm) high
1. Kryptonite New-U Mini-7
This is the Wirecutter's best bike lock. And there's a lot to like about it. The 13" shackle is made from Kryptonite's top of the range max performance steel, making it stronger than some of their older u-lock shackles.
The 7" internal height will give you loads more locking positions in a bike rack than any mini u-lock. For example you should be able to get it around the tire and the down tube on many bikes.
And it comes with a steel cable to secure your other wheel. Although these cables can be cut very easily, they do provide some (mostly psychological!) protection.
It's important to note that 2 stars from ART generally puts a lock at the lower end of the Sold Secure Gold rating; most 2 star locks are actually rated Silver.
For sure: the max performance steel and double locking shackle mean that the New-U Mini 7 is a high security u-lock but the fact that the shackle is a circular 13 mm, makes it slightly less secure than the other high security options on this page.
However, it's a nice all rounder that is relatively light whilst still being very secure and comes with Kryptonite's great after sales care. So you can buy the New-U Mini 7 [Amazon] with confidence!
2. OnGuard Pitbull Medium
This medium version of the Pitbull is OnGuard's rival to the Mini-7 (although I think the OnGuard lock came first).
It's slightly wider which potentially gives you a few more locking options. But it's still unlikely you'll be able to secure your bike anywhere but a bike rack.
And it has a slightly thicker 14 mm shackle that is sure to be at least as strong as the one on the Kryptonite lock.
The mechanism may not be as un-pickable as it's rivals and for sure it will need more regular cleaning and lubrication.
But the big advantage of this u-lock (like all OnGuard locks) is that you can pick it for a much cheaper price than other brands. So if you're looking for a high-security, budget medium size u-lock, the Pitbull Medium [Amazon] is a fantastic choice.
3. Seatylock Mason 180
The first thing you notice about the Seatylock Mason 180 is the triangular shackle with a 17 mm diameter! This clever design keeps the weight down while completely thwarting all bolt cutters.
The Mason is just ever so slightly longer and wider than the Mini 7 so it will give you more or less the same locking options.
And it's received the same Sold Secure Gold rating as both it's rivals. But the 17 mm triangular shackle probably makes it more secure than both of them, against brute force attacks at least.
To keep the cost down there's no frame mount supplied with the Mason. But you can buy one separately. And it's highly adjustable so you should be able to find a position that works on any bike.
The Mason is around the same price as the Mini 7. And if a thicker shackle will give you that extra peace of mind then the Mason 180 [Amazon] is a good alternative!
The 3 Best High Security Mini U-Locks
These locks are smaller and easier to carry than the Standard size u-locks. But be careful with the Fahgettaboudit, it's heavier (and also more secure) than all the other locks on this page! In no specific order...
14 mm shackle
3.13 lb (1.42 kg)
3.55" (9 cm) wide
5.52" (14 cm) high
X-Plus 54 Mini
13 mm shackle
2.56 lb (1.16 kg)
4.23" (10.8 cm) wide
5.51" (14 cm) high
Kryptonite New York Fahgettaboudit Mini
18 mm shackle
4.55 lb (2.06 kg)
3.25" (8.3 cm) wide
6" (15.3 cm) high
1. OnGuard Pitbull Mini
There is a mini version of the OnGuard Brute Standard, with the same super strong, (albeit shorter), 16 mm shackle.
But while the Pitbull Mini's 14 mm shackle does make it a little less secure than the Brute, since it also makes it significantly lighter, I think it's a good choice for those looking for an easier to carry option.
And in fact the Pitbull has the same quadruple locking mechanism and the same Sold Secure Gold rating as it's big brother. So it remains extremely secure!
Like all OnGuard locks it's incredible value for money but needs regular cleaning and lubricating at both the lock mechanism and the ends of the shackle to keep it working nicely.
So if you're after a bargain priced mini u-lock that offers some of the highest levels of protection available, the OnGuard Pitbull Mini [Amazon] is a great choice.
2. Abus Granit X-Plus 54 Mini
The Abus Granit X-Plus 54 Mini is a miniature version of my favorite bike lock, the Abus Granit X Plus Standard.
It features the same parabolic 13 mm shackle. And it has the same Sold Secure Gold and ART 3 Star security ratings, (although it adds an impressive Motorcycle Gold rating too).
However it's much shorter. And it's much lighter. In fact it's one of the lightest high security bike locks currently available.
And while it's not cheap, the high build quality means that not only is it very secure, it's also extremely reliable.
So if you're after a maximum protection, while remaining light, practical and dependable in all weather conditions the Abus Granit X-Plus 54 Mini [Amazon] could be the right u-lock for you!
3. Kryptonite New York Fahgettaboudit Mini
The New York Fahgettaboudit Mini is the only bicycle u-lock with a 18 mm thick shackle and it's undoubtedly the most secure bicycle lock available today.
At 3.25", it’s pretty narrow. But 6 inches in height makes it the longest of the three mini locks. It’s double bolted, is the only bicycle U-lock that gets Kryptonites 10/10 security rating and is eligible for anti-theft protection up to $4500 / £2500.
However, ultimate security comes at a price. At 4.55 lbs (2.06 kgs), the Fahgettaboudit is much heavier than it’s two rivals. In fact it’s the heaviest lock on this page!
It's also quite expensive.
But if you want the very best bicycle security available today then this is without a doubt the best u-lock for you. Read my full review of the Kryptonite Fahgettaboudit Mini u-lock.
The 3 Best Mid Security Standard Size U-Locks
These medium security standard size u-locks will give you loads of locking options and will be easier to carry than their high security cousins. They can be defeated by the biggest bolt cutters and some leverage attacks but if your circumstances are lower risk, they're a a great, practical choice. In no specific order...
Kryptonite Kryptolok Series 2 Standard
13 mm shackle
2.84 lb (1.29 kg)
4" (10.2 cm) wide
9" (22.9 cm) high
13 mm shackle
3.07 lb (1.39 kg)
4.5" (11.5 cm) wide
9" (23.0) cm high
Plus 640 230
12 mm shackle
2.34 lb (1.06 kg)
3.27" (8.3 cm) wide
9.0" (23 cm) high
1. Kryptonite Kryptolok Series 2 Standard
The Kryptonite Kryptolok Series 2 is the classic U-lock. The 13 mm shackle should defeat all but the biggest bolt cutters. And it gets a respectable Silver security rating from Sold Secure and 2 stars from ART.
It’s really well made, dependable and benefits from Kryptonite's renowned after sales care which includes optional anti-theft protection up to $1500 or £800, replacement keys, and a full refund if your key breaks in the lock.
The only downside is a frame mount which some people say doesn't adequately support their lock. However I think this is often a case of poor installation (either through confusing or misread instructions). If it's installed correctly it should do a good job on most bikes.
It's important to note that there's now two versions of the standard sized Kryptolok. This one has a "bent foot" shackle which only locks on one side (hence the Silver rating).
The other version: the New-U Kryptolok Standard [Amazon] has a shackle that locks on both sides (plus other minor differences) and is rated Sold Secure Gold.
Both locks have the same dimensions, weigh more or less the same and will cost around the same price so it makes sense to get the Gold version if you can!
However the Gold version retains the 2 star rating from ART which indicates that it sits at the lower end of that rating and I'd suggest it remains a mid security u-lock.
So if you’re looking for a practical bike lock for low to medium risk areas from a company that offers great customer service, the Kryptolok [Amazon] could well be the best U-lock for you. You can read my full review of the Kryptolok here.
2. OnGuard Bulldog Standard DT
The Bulldog is OnGuard's equivalent of the Kryptolok. It too features a 13 mm shackle and a Sold Secure Silver security rating. And it’s also slightly lighter and cheaper than the Kryptolock!
The slightly wider shackle will probably give you a few more locking options too.
However, OnGuard's after sales care isn't a patch on Kryptonite's. And you'll need to clean and lubricate it more often to prevent it sticking.
But it’s such a good value, if you’re looking for practical protection in low to medium risk areas at a discount price, then the Bulldog [Amazon] could well be the best U-lock for you. Read my full review of the Bulldog here.
3. Abus Granit Plus 640 230
The Abus Granit Plus 640 230 is the lightest of the 3 locks here. It achieves this my making the shackle 1 mm thinner and significantly narrower than the other locks.
However it retains the same Sold Secure Silver security rating. So this is a good choice for those who really value weight savings without sacrificing protection.
It's true, the narrow shackle could make it more difficult to lock your bike up in certain situations. But don't forget: it also makes the lock more secure!
Like all Abus locks it's built to last. So if you're looking for a very light, standard size u-lock that still offers plenty of protection and dependable performance for many years to come, the Abus Granit Plus 640 230 [Amazon] is good choice!
The 3 Best Mid Security Mini U-Locks
These mini u-locks would make easy to carry primary locks in lower risk circumstances or very secure secondary locks in higher risk circumstances. In no specific order...
11 mm shackle
1.65 lb (0.74 kg)
2.75" (7 cm) wide
6.0" (15.2 cm) high
13 mm shackle
2.2 lb (1 kg)
2.75" (7 cm) wide
5.3" (13.5) cm high
Plus 640 150
12 mm shackle
1.76 lb (0.80 kg)
3.27" (8.3 cm) wide
6.0" (15 cm) high
1. Kryptonite Evolution LITE Mini-6
The Evolution LITE Mini-6 is a relatively new addition to the Kryptonite range. It boasts a 11 mm hardened MAX-Performance steel shackle that has the same strength as the 13 mm shackles of the Evolution Mini-5, Mini-7 and Mini-9.
This means it’s as strong as some 13 mm locks but a fraction of the weight! Indeed, at 1.65 lb (0.74 kg), the Mini-6 is also the lightest of the 3 locks here, despite having the same dimensions and security rating.
And although it’s not double bolted, you do get the famous bent foot design which makes it easier to use, 3 keys (one with LED light) and Kryptonite's optional anti-theft protection up to $2000 / £900.
Although it has the same Sold Secure rating I do think the other two locks are likely to offer more protection due to their thicker, double locking shackles. But this is the super light weight option.
It’s also very reasonably priced! So if you’re looking for a strong, light, good value secondary lock that could be also used as a primary lock under some circumstances, the Mini-6 [Amazon] may be the best u-lock for you.
2. Hiplok D Mini
Most mini u-locks (including the three here), don't come with a frame mount. I suppose the idea is that they're so small and light that we don't actually need one.
So people generally throw them in a bag, hang them through a belt loop, or shove them in a back pocket.
However for many people this isn't possible. What happens if you don't have a bag or belt loops and your back pockets aren't big enough?!
Hiplok have realized this and all their locks are wearable. Their u-locks have a belt clip built into the crossbar which allows you to attach them to whatever you're wearing around your waist. Or the outside of your bag (keeping the inside clean and dry).
I love this idea. In fact I tested their high security version the Hiplok DXC and thought it was a great lock.
The Hiplok D mini is their mid security version and is the same but with a slightly thinner (13 mm) shackle. The shackle does lock on both sides though. And the lock features a solid Silver rating from Sold Secure.
So if you don't like regular frame mounts and don't have an easy alternative way to carry your bike lock, the Hiplok D [Amazon] is a great mid-security, mini u-lock which could be the best choice for you!
3. Abus Granit Plus 640 150
This lock is simply the mini version of the Abus Granit 640 230 that I recommend above. It has the same 12 mm thick, double locking shackle and the same Sold Secure Silver rating. It's just much shorter!
The great thing about this lock is that it provides significantly more internal locking space than the other two locks without being heavier or sacrificing security.
It's much wider and taller than the Hiplok while also actually lighter! And it's much wider than the Mini-6, (and the same height), while being only slightly heavier despite having a thicker shackle.
More internal locking space means it will be easier to find somewhere you can lock your bike up and this is important with mini u-locks as options are often limited by their small size. So every bit extra helps!
Beyond this it displays the usual Abus high build quality which means it will be dependable in all weather conditions and should last many years to come.
Like all Abus locks it's not cheap! But if that extra locking space in a mini u-lock is important and and you value long lasting quality, then the Abus Granit Plus 640 150 [Amazon] is a great choice!
U-locks are probably the best way to protect your bike in the street, offering the nicest balance between security, price and practicality.
But choosing the best u-lock for your bike is a very personal decision that will depend very much on your individual circumstances.
If your circumstances are high risk then you'll need a high security u-lock. But u-locks that offer high levels of protection are heavy and bulky.
Whether you can mitigate these drawbacks with a smaller u-lock will depend on what type of bike you ride, how you want to use the lock and where you'll secure your bike.
If your circumstances are lower risk then you'll probably be able to get away with a medium security u-lock. They're usually lighter. But you'll still need to pick one that meets your other individual needs.
If you're unsure about which security level you need, it's better to be cautious and go for a more secure option. It will give you peace of mind and if you buy a more desirable bike you won't need to upgrade your lock at the same time!
I hope this page has helped you to find the best u-lock for your needs. You should also check out my article on wheel and seat security.
And don’t forget to make sure you know how to lock your bike properly too!
If you have any comments, suggestions or questions, please let me know below…
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Not much know but somehow this lock seems to resist all that bad tools: https://www.litelok.com My bike is still at home, just can’t find proper (best) solution… Btw. Would be great if you could cover some of a GPS tracking and alarm systems. Seems to be cheaper than most of these locks and systems…
The Litelok looks great doesn’t it! I preview it here, and I’m looking forward to trying it out when it’s released.
I’d like to review some of the GPS systems too. Another thing to add to my list!
I wonder what your review would be of Tigr titanium lock. They make several but my husband and I have the two versions of the Tigr mini and mini plus. I also have an Ottolock as a supplement to add. I believe the two together are much lighter in weight and may provide more security. Would be interested in your thoughts.
That’s an extremely lightweight security set up you have there!
I’ve already tested the TiGr mini and like it a lot. You can read my review here. It’s not super high security but it’s a great choice if weight and ease of transport are important and your risk level is not so high.
How are you finding the Ottolock? I’m really keen to review it. Seems like it might be a great choice for securing wheels or even as a cafe stop lock for racing cyclists.
Thanks for the info! I’m new to the bike scene and I’ve recently bought a road bike. Had no idea what kind of lock to buy, but now I’m pretty set on a U-lock. I’m eyeing the OnGuard Brute. Any chance you know the ETA of the full review for this lock? Many thanks!
I’m not sure when I’ll be adding a full review for the OnGuard Brute. But I can say now that it’s a fantastic lock.
It’s probably the best value, high security lock available at the moment. A 16.8 mm shackle that can’t be cut by any manual bolt-cutters. Double-bolted. Sold Security Gold. And at the moment you can pick it up for around $50 or £24. That’s incredible value if you ask me.
You need to check the weight is OK for your needs as it’s pretty heavy. And make sure you give it a regular clean and lubrication. But you can buy with confidence!
thank you for your reply! I’m definitely going to stick with the OnGuard Brute.
Abus u Lock broken in seconds
This is just a few words of advice regarding bike locks.
Today, I returned to my bike to find the lock battered and smashed but luckily still in 1 piece. Unfortunately, the key would not longer fit in the lock so I had a small problem!
I managed to contact local security and after showing some ID they produced some bolt croppers and cut through my expensive ABUS lock in about 10 seconds!
My point is – any non D-lock style lock can be cut in seconds with bolt croppers. My ABUS lock cost £30 and I thought it was pretty tough. Luckily it saved my bike this time but after seeing the ease at which it was cut I’ll not use a similar one again. It was a thick braided cable cover in hardened steel shells.
I know d-locks can be broken too but not quite as easily. Take good care of your bike and get a decent lock!
Yep, even the armored cable locks like yours are very easily beaten. This is why I won’t recommend them. As you say a decent U-lock is usually the way to go. They are generally the most resistant to bolt cutters. But a good chain can also do the job, depending on your circumstances and the way you lock your bike.
Anyway, at least you still have your bike!
Can you remember which model of Abus lock it was?
I locked my semi decent older road bike (pre fixie craze which would make this bike a prime target now) with a braided cable lock which was about 3/4″ thick. I would put it under a street light locked to the same telephone pole support cable. The lock had a heavy vinyl covering which had battle scars ….several bolt cutter notches in it from multiple attempts to cut it. I switched to this lock after the whole kryptonite BIC pen fiasco where kryptonite took my info but never followed up on replacing my lock. I often wondered if the kryptonite U lock would have saved my bike on those attempts.
First of all, thanks a lot for the great reviews and suggestions.
With their help I decided to buy an OnGuard Brute LS-8000, which is the big brother of the STD-8001. I use it along with a 7mm Abus chain like in the pictures from the links bellow. Just wanted to ask your opinion regarding this setup, especially the U-lock. Does it look too loose, allowing a potential thief to take advantage of that space in order to force the lock somehow or I’m fine like this?
On the other hand, the pole is pretty thin and the bigger U-lock might come in handy on some bigger poles. Also, my frame is a bit wider and the STD-8001 barely fits and presses unnaturally against the wheel.
Appreciate your help regardless of you providing an answer.
As a side note, I plan to only take the small chain with me during day time rides. People around here apparently mostly use wire “chains” so this gives me a little more confidence.
I think you’ve done a pretty good job there! The OnGuard Brute is one of the most secure locks available today. And you’ve filled up most of the space inside the lock so it should be safe from leverage and bottle jack attacks.
If you’re worried about this you could try and fit the u-lock around the pedal crankarm as well. But in this case it might not fit. And I think it’s fine as it is anyway.
The 7 mm chain lock is fine as a secondary lock for securing you wheel to your frame and for a bit of extra security around the frame. But I’m a little bit concerned about you using it by itself “during day time rides”. I depends on where you’re riding and how long you leave your bike for and whether it’s out of your sight etc.
But a 7 mm chain can be bolt cropped quite easily. And it’s not Sold Secure Silver (or equivalent) so I wouldn’t recommend you use it in isolation.
As I say though, the set up in the photos looks great. Good job!
Thanks a lot for your reply. It means a lot coming from the guy that built this wonderful piece of lock wiki.
I’ll try to use the u-lock as often as I can and take care of my bike.
All the best and take care!
Carl, your site and this article (along with several others I’ve read tonight) have been exceptionally helpful. Thanks so much for introducing me to 21st century lock products and helping me keep my new ebike more secure.
so i just got the Abus lock above as a 2nd lock and it scares me already. While playing around with mounting options, the key had troubles opening and closing the lock on more than one occasiou. Only time will tell if i’ll be left stranded somewhere with my own lock on the bike. …I searched reviews on this and there’s a youtube video of a guy getting help cutting his own Abus U lock from a bike locked to a high wall/fence. not a good sign. Secondly, the mounting bracket is ridiculously limited. I also feel it slides in backwards. you can turn it around but then the “clever” way of prventing the lock from accidentally sliding off no longer functions. ..it uses the locking bar itself, in locked position, to stop it from shaking off the mount so flipping the slider around disables this.
The Abus 401 Mini or the Abus Granit Futura 64 150?
hmm. my reply disappeared.
summary. it was the mini. the lock holder was an add on purchase. The lock in the video was probably a 40.
then i mentioned another video i stumbled that showed my lock where a guy opened 2 locks with the same key. Again, i totally believe this because the kryptonite evolution 4 had the same problem before they changed the key type in them. I also have first hand experience with this where I had 2 heavy cable locks, bought several years apart, that were shockingly keyed the same. it makes me think the bike lock makers are extremely lazy and probably only have 20 different keys for any given lock. I don’t see how else it would be possible to have locks opening with the same key. I keep meaning to go back to a store to try my various lock keys in all the locks. i would NOT be surprised if i opened one.
The 40 and 401 are two of the Abus locks that are made in China rather than Germany. I’m not sure if that’s likely to effect their quality or not.
It’s interesting what you say about the same keys opening different locks. I have heard of this before. But ABUS claim for example that their X-Plus lock cylinder has 1.4 million key variations!
sk them how many of those 1.4M possible keys are they actually cutting. I’ll bet there are huge cost/manuf. savings in cutting hundreds of the same keys and lock cylinders then shuffling the shipments to differnet cities or stores. …or they could have cases of all unique cylinders, but duplicates of identical cases to be used sequentially in manuf. which would stagger their release to market over several years.
The various lock videos show guys in short uninterupted clips inserting keys and opening multiple locks. Like i said, i believe it, and i could make a video myself because I still have the 2 heavy cable loops that are keyed the same although i don’t use them anymore.
Mmmm it would be interesting to do some more research into this. Can you post links to the videos?
*Ask is the first word. hehe
a search will bring up bike forum posts where other people were shocked to see their key opening 2 locks.
The abus key codes are 4, 5, 6, and 7 digits long. that means they’re using 10000 max key variations for the 4 digit code locks. …and i’d be surprised if all are used and someone has 0000 or 1234, or 1111 etc, the same way license plates do not use all combinations.
Very interesting asdf, thanks. I’m going to do some more research into this…
Yeah, it would be interesting to see what you find out.
It would also be interesting to see what they manuf. have to say about this because it’s obviously a problem they’re aware of. Personally, i do NOT believe the “your lock is old and worn out” reasoning because there are door locks and things that have been around many many decades longer that do not open unless it’s the right key. I have keys for many homes where the same cylinder style is used on several doors and the only key that works is the right one. I suspect it’s a cost cutting measure.
Yes I’m going to try to get in touch with the manufacturers to get some information.
Trying to find the abus 401 mini yellow
To get the gold security rating
In the US, thoughts on where to purchase?
Hard to find
Wiggle have got it at a good price at the moment:
What do you think about the SIGTUNA brand? https://www.amazon.com/gp/product/B016GZWRY4/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
Couldn’t find much information on Google. According to the description on Amazon it’s 16mm, but somebody asked how thick it is under the rubber and they answered 14mm.
Still looks like a nice lock even though it’s a bit heavy and the price is not bad at all.
Well it’s definitely cheap Yariv.
But it hasn’t been tested by an independent security organisation. And from reading the reviews it seems that not only is the metal shackle 13.8 mm rather than 16 mm, but someone was able to cut through it very easily with a pair of bolt cutters (because the key had failed).
This suggests the steel is probably poor quality.
So on the plus side, it’s cheap and it looks really strong (which will be enough to deter most casual thieves). But on the negative side you have to carry around something that’s very heavy and that’s probably not very secure in reality.
And for less than $10 more you could get the OnGuard Brute which is genuinely 16 mm and is Sold Secure Gold certified. (Although no frame mount or cable with the Brute).
Thanks for the reply! (glad I came back to check, no email notifications?).
You’re right, I’d rather invest in a better lock. From the comparison chart seems like the Abus U-mini 401 is the lightest Gold rated lock, and right after is the OnGuard PitBull mini. Price-wise the OnGuard seems like a better deal. Do you have any preference?
Actually found another one of your awesome articles and you clearly recommend the Granit X-Plus 54 mini (https://thebestbikelock.com/best-bike-lock/lightweight-bike-locks/).
Prices for Abus locks are double but probably worth it.
Yes, the Granit X-Plus 54 mini and the OnGuard Pitbull mini are both great locks. The Abus is lighter and probably a little bit more secure. The OnGuard is obviously much cheaper. Either one is a good choice.
But I’m not sure about the Abus U-mini 401 Yellow anymore. I don’t think Abus still making it. I’m not convinced by the build quality. And I’m not even sure the weight I attribute to it is correct! I think the other two are better options.
I hope that helps!
I’m just looking for a budget lock for my 3-year-old bike. Mine just broken last week. I use the lock when I go to school and I don’t need an expensive lock. I searched on amazon and found several more cheaper locks such as this Enkeeo Bike U Lock (https://www.amazon.com/dp/B01GR6BFNG), it is stated to be made of heavy duty hardened steel with protective PVC coating, another one is DTLA Bikes U-lock with high temp conditioned high strength steel. I wonder if either of them could meet my daily use.
I would be very wary about claims that these locks are hardened steel. They’re almost certainly not. And if you read the reviews a couple of people seem to confirm that.
The first thing you should think about is what degree of security you need rather than what sort of budget you have.
If you’ve decided you don’t need a high security lock, then how about the OnGuard Bulldog? It’s available for $24 on Amazon at the moment. You can probably even find it cheaper.
It has a slightly thicker shackle. So it’s likely to be slightly more secure. And I would certainly trust it over the two you mention.
I hope that helps!
Could you comment on the use of “freezing sprays?”
Decent U-locks that use good quality steel aren’t really vulnerable to freeze spray attacks. Cheap, low quality U-locks obviously are though. Another good reason to avoid them!
Hello Carl. First of all I would like to thank you for all your articles about bike security, it is really helpful. Also I have no doubt that for me the best standard size U-lock will be ABUS Granit X-Plus 540 due to its weight to security ratio.
But I need some advice on the secondary lock. Initially I planned to buy Kryptonite KryptoLok series 2 995 Integrated 55cm Chain because I thought that for thief it would be more difficult to handle with locks of different types and also for me with a chain it would be easier to lock my front wheel not only to a frame but also to a bike rack (or something else). But due to it weighs 1.77 kg and have only 9 mm in thickness, I thought that it would be better to use some U-lock instead of chain.
So after reading your recommendations about secondary U-locks I decided to buy Kryptonite Evolution LITE Mini-6 because it was thicker than a chain (11mm bar thickness) and much lighter (only 0.75 kg). But after that I found ABUS Granit Plus 640 with 12mm bar thickness and 0.86 kg weight. For me 100 grams difference is not noticeable, but Abus lock is double bolted and it’s a great advantage. Also Abus is a bit wider, which can be useful when trying to fasten the frame and wheel to the rack.
And after that I have read comments to this article about ability to unlock different locks from one manufacturer with a single key. So maybe it is not a good idea to use two U-locks from one manufacturer (Abus in my case) and maybe it is better to choose Kryptonite in order to protect myself from the keys matching?
I would like to know your opinion on this three secondary locks and possible pros/cons of using them with ABUS Granit X-Plus 540. Thanks.
I think that the Kryptonite Evolution LITE Mini-6 and the ABUS Granit Plus 640 are both great secondary locks.
I wouldn’t worry about the key issue. They 640 and the 540 have different cylinders so you won’t find 1 Abus key able to open both locks.
My advice would be to compare the prices. Abus is usually a little bit more expensive (depending where you live). If the extra width and slightly higher security level are worth the extra money go for the Abus. Otherwise go for the Kryptonite.
I hope that helps!
Hi Carl, what a great article, thank you for sharing your knowledge! Like Oleg, I was about to purchase the Kryptonite Evolution LITE Mini-6 but am now considering the ABUS Granit Plus 640, which is a $35 difference.
My questions are: is double bolt security a major factor in thwarting attacks, and does it have any disadvantages (since you mention that the bent foot design is easier to use)
Thanks very much!
Sorry for the late reply Will.
Double bolt security is significant. When implemented properly it means the shackle has to be cut twice to free it. It also offers further protection against leverage attacks.
However I know that some of the thinner OnGuard double bolted shackles can still be worked free with just one cut. That shouldn’t be a problem with the Abus 640 though.
You can reduce the chances of leverage attacks by filling the space inside the U-lock as much as possible. But that still leaves the extra cut advantage of good double bolted shackles.
I hope that helps!
I’m trying to find a decent option for our son that doesn’t use a key, rather a combination. Is that even an option? He’s autistic and tends to lose things (e.g. keys!) so looking for anything that may work!
Combination locks tend to be slightly less secure than keyed locks. However Kryptonite do a combination version of the Kryptolok which I rate highly if your circumstances are lower risk.
Do you think that might be suitable?
Hi Carl, Thanks for the super-quick response. I think that will do the trick! We’re in the suburbs of NorCal and this would be for locking up at his elementary school on the days he can ride in. It’s well covered by cameras and the like so this will deter the casual opportunist.
Thanks again (and great site!)
My husband and I have the Tigr mini and mini plus. They are titanium and very lightweight. I also have an Ottolock to supplement. Would be interested in other’s comments.
Thanks for the very informative website. I just bought my first bike since being a kid (a used road bike for around $350) and I’m looking for a lock to keep it safe. I live in New York City and I don’t plan on keeping it outside for too long. My apartment building has storage indoors as do many of my friends’ apartments.
Right now I’m leaning towards a mini lock. I like the convenience of having a smaller, light lock. Do you think the Abus U-Mini 401 will be okay for me? I’m also looking at the Abus GRANIT X Plus.
I bought the Kryptonite New York Standard but it just feels a bit heavy. I think I’d get used to it after a while but I’m not sure if I’d be gung-ho to bring the lock with me everywhere I go.
I’d love to hear your thoughts.
The Abus U-Mini 401 is a good lock, but it’s made in China and I’d tend to favor the Abus Granit X-Plus 54 Mini if you can get it at a good price.
It’s basically the mini version of the Abus GRANIT X Plus, so you get the same (or in fact more) security as the 540 at a much lighter weight.
It’s slightly heavier than the 401, but I’d say it’s more secure too!
Anyway, that’s definitely the one I’d recommend if you can find a nice price.
Hope that helps!
Thanks for the quick response. I appreciate it! I think the Abus Granit X-Plus 54 Mini is the perfect combination between security, size, and weight. The only tough part is the price but I’m happy to pay for good security!
Lockpickinglawyer posted a video about kryptonite’s newyork lock having no false gates and easy to pick :/
Yeah that’s disappointing. It’s highly unlikely anyone is going to pick your New York lock out on the street in the real world though.
Between kryptonite kryptolok series 2 and onguard bulldog which lock do you think is stronger against hand tool? How does the steel compare between the two?
I would say they’re around equal against hand tools. The Bulldog is likely to resist leverage attacks slightly better since it’s double bolted. But the Kryptolok probably has better steel.
Overall though I think the Kryptolok is the better lock since it’s easier to use and you get better customer support with Kryptonite.
I hope that helps!
Great effort, but why nothing about password (not keys) U-locks? I want to know if they are secure enough to buy one. It’s terrible when you leave your keys at your job, and you are half the way home getting your bike at the train station…
In chain locks (or cables) they’re much less secure as they’re easy to pick or decipher. In U-locks, I think they’re not as un-secure, depending on the lock. Do you have a particular lock in mind?
Are there any U locks which have a spring loaded mechanism where you push the lock barrel on and it locks automatically (like a padlock), rather than having to put the key in and turn it to lock?
Hi, I live in Uruguay, South America, so I have limited choices. Was looking for the on guard brute, and found it, but also the on guard pitbull, which would be best in safety? And which in comfort for carrying? Thanks a lot!
The Brute is a stronger lock than the Pitbull. But it’s also heavier, so it’s a little more trouble to carry around.
Unless your circumstances are really high risk and/or you have a very expensive bike, you should be OK with the Pitbull.
I am in Germany, Cologne. Not sure how the bike safety is in this place, but I ll mostly parking in the city. I have an Ebike and its insured. I am looking to buy a lock for it before I start using it. I want safety but if possible easy to carry. Was looking at the Brute, any other comparable options (safety and price) youd recommend? I have seen a Evolution 7 from Kryptonite, not sure how it compares. Not sure if its double bolted or how much lighter it is.
Also would consider another lock type if it offers similar safety to the Brute. My Only concern with the brute is people saying they are not able to open it after a while.
I thought about using a U Lock and then wrap a light chain lock around, on top, and between the U lock. Not sure if you understand my idea or if itll make it any safer, but in my opinion itd just make their cutting of a 16.8mm much more difficult. Or is it better to put the extra chain elsewhere?
Also do you have any ideas how to secure the battery (rack)? Thats the only thing id be worried about in the city here, at first sight, everything seems quite safe but I am not sure.
So sorry John, I somehow missed your comment.
The Brute is a good lock. But you do need to apply grease now and again to the ends of the bars (that attach into the body of the lock). If you remember to do this you should be OK. You might as well use a Teflon based lubricant on the mechanism at the same time!
The only way the Brute is likely to be defeated is with an angle grinder or a leverage / bottle jack attack. Wrapping a smaller chain around the and through the U-lock won’t protect you from an angle grinder. But by reducing the space inside the U-lock it can certainly protect you from leverage attacks or bottle jacks.
I’m not sure about protecting the battery rack. Could you post a photo of the bike?
Hi Carl! No problem, I understand! It happens 🙂
Here you go, pictures of the bike in general and the battery. https://www.dropbox.com/sh/g7i62qymu7hedti/AAAZBz6DZrlZq1WJPhAFmuLga?dl=0
Its my first bike, so I dont really understand much of the related things. I am just going crazy with anxiety thinking of what I could be doing wrong or with selecting the right lock among all the selection. Bought the Brute, got it yesterday and havent used it yet. Its 20cm long, its looking a tricky to use it the way I thought I have to. By inserting it trhough the back wheel and frame. Since the width of the lock is just about 11cm, for some reason I thought my wheel and the frame next to it was about that size (when you insert it from the side rather than along the, not sure if I explain myself well there) but instead that part is about 14cm. Took the bike down to the street, in front of my building and tried testing parking my bike there. It was a bit tricky as I had to do it along the bike direction and the twist the lock to the side a bit to catch the street pole.
My question is, whenever i dont manage to do this. Is it safe to place just against the bike frame? For example the thicker middle park, where you have the brand name “Fischer”. The wheel at the back has its own built in lock.
Also would you recommend keeping the locking mechanism up instead of down? Thinking of that if someone uses a hammer against the mechanism its more difficult if its up. Not sure!
Sorry for all the questions, but one of the last one is. What extra as the secondary lock would you recommend and how would you use it on my bike? Been trying to find a chain, not too heavy and not too thing but its been hard. Most are 6mm and I heard that is pretty much useless. Seen an Abus Steel-O- Chain for about 30 euros, 7mm. Felt a bit heavier than I would want and not sure if it really adds safety with 7mm. Hopefully you have some ideas of a maybe better or lighter/cheaper lock idea.
Last one is: How would you lock my bike if you were using, best case scenario, with the Brute and a secondary thing.
Thank you so much! For all the time you take answering all of our questions.
This whole bike theft thing is driving me crazy. I still havent used my bike because of all this.
It really depends on how risky the area is and how long you’ll be leaving it for.
Since your rear wheel has a frame lock, you should be OK leaving the bike just locked around the frame. But what about the front wheel? Do the wheels have quick release skewers? It’s hard to tell from the photos.
Keeping the lock mechanism downwards will certainly discourage people trying to interfere with it.
As for a secondary lock, it will depend on what your going to lock with it. The front wheel? The battery pack?
If your wheels are quick release or use regular nuts (so anyone can remove them), I’d be tempted to replace them with secure versions. Hexlox are my favorite. But the gravity ones from Kryptonite, Abus or IXOW are also good.
This would keep the weight down.
If it’s for the battery pack then it’s difficult to tell what would work from the photos.
But my view is: with the Brute, the frame lock on the back wheel, and some secure skewers/nuts you should be OK. As long as the battery pack is not easy to remove and desirable to a thief!
Wow, I have just the list of Chains too! Awesome, will take a look while I see if you recommend something specific ! Once again, great stuff man. Thanks for the website
Great info on the site, a little overwhelming considerations for just a lock but I believe it’s worth the research.
I just bought my first road bike, this Specialized Allez:
I know you recommend getting a secondary lock, but would a U-Lock with a complementary cable be secure enough to say lock the bike near a public park for 3-4 hours? I don’t know if I would ever need to lock my bike any longer, 6 hours tops.
I prefer a lightweight lock that will fit the parts on my Spec Allez and budget friendly if possible
Thanks for your awesome site!
Nice bike Chase!
I would definitely be using a Sold Secure Gold lock on a bike like that. And 3-4 hours is a fair bit of time for it to be left alone by the way.
If the wheels have quick release skewers then a complimentary cable definitely won’t be enough. If you’re worried about the extra weight of a secondary lock, I’d recommend that you replace the quick release skewers. You can read more about this on my wheels and seats page.
I hope that helps!
Bought the Kryptolok series 2 only to find out it doesn’t fit with my water bottle inside my triangle frame. Also, I went back and looked at the reviews on Amazon and there were 500 critical reviews, many of which complained of their bike being stolen.
I will be returning the Kryptolok and looking for a better alternative that is light, Sold Secure Gold this time, and fits in my frame.
With these parameters and using your spreadsheet, I’ve narrowed it down to the Litelok and the OnGuard Pitbull mini, however in all likelihood I’m not going to fork over $140 for the Litelok.
I’m hesitant to grab the Pitbull mini as I’m not sure how limited the locking options will be in reality. I’m guessing anything over 3″ thick would not work with the mini u-lock.
Any recommendations or advice would be greatly appreciated.
Sorry Chase, I answered your previous post without seeing this one.
The OnGuard Pitbull Mini would work well with secure wheel skewers as you’d only have to worry about securing the frame (rather than the frame and the wheel).
Thanks for the response.
So I checked out the wheels and seat security page and was really sold on HexLox by its elegant design, albeit not too thrilled to rid my new bike of the innovative quick release skewers that make wheel adjustments so quick and easy, but it would at least mitigate if not eliminate the associated anxiety of leaving your bike exposed to even the most simpleton thief who wants your desirable wheels and can have them in 5 seconds with a flip of the lever.
Assuming for the time being I just take the front wheel off and lock it together with the back wheel and the frame, eventually pulling the trigger on some HexLox skewers and possibly the full protection Kit, which frame lock would you recommend for both this short term and long term perspective?
It looks like the Pitbull mini may well do the trick.
After doing some more digging, the Pitbull mini is too small, but moreover the majority of Onguard reviews on Amazon mention degrading shell parts. I’m going to avoid this poor manufacturing quality.
I did lots more digging and have landed on the Kryptonite Evolution Series 4 as a cheaper alternative to the Abus Granit X 540. The sticking point for me is its heavy weight, but the next best alternative that offers the same security but lighter weight would be the litelok at double the price tag…:/
The Kryptonite Evolution Series 4 is a great lock. But I’d imagine you’re quickly going to get fed up removing your wheel every time you lock your bike up. And then once you buy some secure wheel skewers you won’t need such a big lock and the additional weight will be even more annoying (and pointless).
If you’re worried about weight and think the secure skewers are a good idea, better to get them now, along with a smaller, lighter lock. That would be my suggestion anyway 🙂
Thanks for the replies, your feedback is amazing really.
I think it’s highly likely someone would boost my front wheel in the places where I usually park it, and the skewers would be even more overkill after mulling this over for a few days.
I’m leaning toward finding a good deal on the Kryptonite Series 4, maybe even add the complementary cabling just to deter the thought of stealing the front wheel. I do realize it can be cut.
The Abus U-mini 401 Yellow seems to have disappeared as of July 2018 – who knows where it went? I don’t see an obvious successor product from Abus.
It’s still available Greg. It probably depends where you live. I’d actually recommend the Abus 54 Mini over the U-Mini 401 Yellow though these days.
Carl…do you have any insight on the Pragmasis DIB D-locks? Came across them as I was looking for the “best chain”.
I’ve haven’t used it Norm. But the Pragmasis guys know what they’re doing (I’m a big fan of their chains), so I’m sure it’s a great lock and a good choice if you’re looking for high security protection!
Great site, it helped me to choose the Abus Granit X 540 as a first lock, I haven decided yet what will become my second lock. Or rather third lock as I will be fitting a ring lock on my bike because that’s pretty standard bike security in The Netherlands :>).
By the way, I noticed that your site does not mention AXA locks, those are hugely popular in The Netherlands:
Would you recommend another U lock as a third lock? From another manufacturer?
It really depends on your bike and your risk level. A good Kryptonite chain like the Evolution Mini might be a decent choice.
You’re right I don’t mention AXA locks. Not because I don’t rate them, ut’s just that I don’t have any experience of them.
Would you recommend them?
Axa ring locks are extremely popular in Holland /The Netherlands. Me, my self and I ( great 80’s ?song) will always buy an AXA ring lock as a first line of defence, for us Dutch cheese heads it is a no brainer. My additional locks have always been Abus U locks and / or Abus chain locks. You know, solid German engineering. Not cheap but OK, one pays for quality. Fair enough.
Nowadays though, with regards to for example the ART rating system, AXA locks and other brands like Pro- tect are so much cheaper than say Abus, and Kryptonite.. while offering the same “protection” or even better…
For me that is confusing..
I think that while the security may be equivalent, sometimes the construction / finish isn’t which can lead to durability issues…
I saw this lock for 22 eurs. It has ART 4/5 rating. A Dutch lock that I saw in a local shop in Brussels Belgium: Stahlex 448 U-Lock 180x245mm
I asked me salesclerk what he knew of the lock and the price for ART4, he said that you’re not paying for a well-known brand 😉
What are your thoughts on this lock?
P.S Here is the lock on ART’s web site:
P.P.S Dimensions listed here:
And with Google Translate:
And a Dutch website like yours, and in English 🙂
Wow, that’s a really good rating. You don’t see too many u-locks with ART 4. This is more of a motorcycle lock though. It’s got a 18 mm shackle and weighs nearly 1.5 kg.
Sometimes these locks are cheaper because (although they are very secure) the components are not very high quality and they start to jam or seize up over time. However all the reviews for this one seem positive.
I would only recommend it as a bike like in the most extreme situations though.
I think 1.5kg is ok to put in my rucksack.
I have a 2.1kg chain lock wrapped around the front of the frame.
Should be baring someone with an angle grinder… 😉
It cannot be worse than my ABUS City Chain X-plus Granit chain lock which broke after locking it 11 times. Bye bye 101 Euros….
I’ll be sticking the the Ulock above. At least when it breaks my loss will be 35 euros instead of 101.
I got this lock recently, and I can confirm it weighs about 1.5 kg (mine weighs exactly 1.51), but the shackle is actually 16 mm (18 mm with the rubber coating). It sure looks and feels like a high quality lock, while also being noticeably lighter than the Kryptonite New York Standard (mine weighs 1.82 kg), but with the same size and level of security. Maybe the Kryptonite NY “New U” version is a bit more secure, because of the new anti-rotation feature, but I certainly prefer to take this lock for high risk areas because it’s lighter and has the same rating, size and thickness as the Kryptonite NY. It’s also much cheaper!
Update an earlier comment: my Abus lock works again. I was using the wrong key. Please, no comment!
The Stahlex is still doing double duty with the Abus for my BMX in the rain. The Stahlex has a little door that slides shut covering the lock keyhole & protecting it from the rain.
I am still very happy with both locks.
first of all thank you a lot for this massively informative post and your effort answering all these questions! And btw: nice name! 😉
I, too, have a few questions since i’m looking for a suitable u-lock as well as a secondary lock for my bike. I’m living in Germany in a medium-sized city which is located directly at the border, so it’s obviously a nice place for bike-thieves. I have been living there for 5 years now and I was fortunate enough that my previous bike wasn’t stolen in this period. The bike was a cyclocross with medium-good components from Shimano and I secured it with only one lock: the Abus Granit X-Plus 540 (respectively the corresponding version of it that I bought 5 years ago). Nevertheless, I bought myself a real high-class bike now, which made me thinking that i probably should level-up in the way I secure my bike.
My thoughts thus far are the following: u-lock to lock the frame and rear wheel to a stationary object and a folding lock to lock the front wheel with the frame to a stationary object.
I consider a folding lock as the secondary lock because I heard somewhere that often thieves specialize in breaking a specific lock type and/or locks from a specific manufacturer. So my first question would be: do you think that’s true? And if yes: Is that a factor worth considering or should I just take a second u lock as secondary lock since they have a higher security?
Regarding the u-lock to secure the rear wheel, I’m considering the Abus Granit X-Plus 540 and the Kryptonite New York Standard. I was absolutely satisfied with the Abus in the past, but since the Kryptonite is thicker i’m wondering if the Abus would indeed be the right choice. Moreover, repeating the argument/story from above: if it’s true that thieves specialize in breaking locks of a specific manufacturer it would probably be clever to have two locks from different manufacturers. And since the Abus folding locks are quite superior (right?), i would have to buy the kryptonite for the rear wheel. Do you have a personal favourite between these two locks? And what are you thinking about my thoughts in general? Too complicated and paranoide? 😀
I’m sorry for the long text – hope you’ll anyway find some time to read/answer it. Anyways i’ll stay a follower of this website and your posts! Thanks again for your effort!
While it may be true in (rare) cases that some thieves specialize in particular lock brands, it’s more likely just the same type of lock.
And it’s less about “specialization” and more about the fact that the thief only usually carries one tool. And that certain tools are more suitable for certain types of locks.
A long iron bar is good for breaking u-locks but not so good for breaking chains. If the thief has an iron bar and you use 2 u-locks, he can rob your bike. If you use a u-lock and a chain, he can’t!
So that’s an argument to use different types of lock. But it also depends on how secure they are! So I can’t tell you definitively to which option to choose.
I really like the Abus Granit X-Plus 540. It’s not as thick as the Kryptonite, but I think it’s just as secure and it’s also lighter.
And if your thinking about 2 locks (both of which go around your frame and wheel), you should also be thinking about weight: it’s a fair bit of weight you’ll be carrying around.
But I think you’re on the right track: the Abus Granit X-Plus 540 and a Bordo or Foldylock are a good combination.
Thanks for this info-packed article. What I’m looking for, unfortunately, I don’t see here. Perhaps you can steer me.
I’m now locking an inexpensive mountain bike in the city with a wider distance between the front wheel rim and the frame than I always had with a touring bike and I want the extra width for flexibility in pole locking, so I need a U-lock that is at least 10″ long and at least 4.5″ width, preferably 5″. Is there such an item out there of reasonable thickness? The bike is not expensive, so I don’t need maximum security at all. If it gets stolen, it will be a hassle to replace cheaply, but not the end of the world.
Sorry about the delay getting back to you. If you go to the u-lock comparison page and click on the “Height” column to order by height/length, you’ll see quite a few locks that seem to meet your requirements:
Abus Granit Strato 61 300
OnGuard Pitbull LS
OnGuard Bulldog LS
However I think the OnGuard measurements are total rather than internal. So they may not work for you. And that only leaves the Abus!
Are you sure you need 10″ length? Because the 9″ Kryptonite ATB are wide enough and are a popular choice with mountain bikers.
Hi Carl, some Kryptonite locks have become a little confusing and I have a somewhat difficult question. The New U Kryptolock (formerly Series 2) has a Sold Secure Gold rating, but is rated 6/10 by Kryptonite, while the New U Evolution Lite Mini-6 and Messenger Mini have a Sold Secure Silver rating, but are rated as 7/10 by Kryptonite. So which lock would you say is stronger? And do you think the gold rated Kryptolock would be appropriate for high risk situations, even though it’s rated only 6/10 by Kryptonite? I’m considering the ATB model because of the width and the gold rating, but the 6/10 rating makes me a little worried because they recommend it as “moderate security”.
Yes I agree, it’s totally confusing!
The difference for Sold Secure seems to be the double locked shackle (the Gold rated Kryptolok has it, the other locks have the bent foot shackle).
And since twisting attacks (which the double bolted shackle is more likely to resist) are one of the commonest methods in trying to break u-locks, this strikes me as significant.
Also the steel may be stronger on the new locks but the shackles are thinner.
So I would say that the Gold lock looks stronger. Although as always your locking technique will make a a big difference!
However, even the Gold Kryptolok is not a super high security lock. If you’re concerned then the Evolution Standard, Mini-5 or Mini-9 might be better choices.
I hope that helps!
Thanks Carl, I really appreciate your insight and your suggestions!
Your charts above show that the OnGuard Pitbull Medium weighs less than the Mini. How can this be? Is there a typo in one of the specs? Thanks for checking.
Fixed! (good spot, thanks)
Hi! I am about to buy a U-lock for my bike and your articles have been the more informative and easy to understand so far, thank you so much for all the info… it has been incredibly helpful. I just have one doubt; after reading this article and checking in amazon I am drawn to buy the Seatylock mason due to weight-size-quality-price but my concern is that since it isn’t as known as kryptonite or abus there are few reviews on amazon regarding their performance. Do you know if the mechanisms are good quality for longterm use? Do you know any negative comments for the brand and/or model? Should I go ahead and but the Abus granit instead since it is a well known brand? Any advice will help; the difference in price is less than $10.00. Thank you so much in advance for your answer
Hi Misha, Which Abus are you comparing the Seatylock Mason to? The Granit Mini 54 or the Granit X-Plus 540? Thanks
To the Granit X-Plus 540, the mini one gives me doubts because of the size, I feel like I will have a hard time finding a suitable location to lock it to. I feel like the Seatylock Mason has a height that is between a standard size Ulock and a mini ulock. But maybe the difference is not that much. What do you think?
Thanks so much for the info and for replying (:
Well they’re both great locks.
Whichever you choose it’s a good idea to clean and lubricate both the mechanism and the shackle occasionally.
I do think that in general Abus are more reliable than any other brand. But the Seatylock seemed good quality too when I tested it.
Remember the Mason, (although it’s a medium size lock), is as narrow as a mini lock. So you’ll still be limited to bike racks. But the Abus is a fair bit heavier.
So it depends what’s more important to you: weight or locking options.
Thanks so much Carl for your answers… this site has been very informative, I will compare both of them a last time and check dimensions with my bike to see what size better suits my needs (:
Thanks for the great line-ip. I’m looking to replace the lock on my gravel/CX bike. I fitted a regular European frame lock (like the Axa Defender) to it since I had the holes in my frame for it. However, at 700gr it’s a little bulky to carry it with my every day while it’s mostly stored at home locked in a shed, or inside at the office at work.
I do like to bike a lot and sometimes park it in the city when I’m in a store for a few minutes. What kind of lock would you advice? I want it to weigh max around 1kg (can be a bit more ofcourse) to keep it light to carry with me. The most important thing is that I can easily carry it with me. So it has to be possible to either wear it like those hiplocks, or it has to be mounted to my frame.
So far I’ve found these: Kryptonite Evolution, ABUS U-Lock Granit X-Plus 540, Hiplok D, Seatylock Mason, and Kryptonite Messenger Mini.
Not U/D locks, but I also found the Abus Combiflex (but looks really easy to cut through) and the Hiplock Lite. The Hiplock can be carried around your waste and seems a little more sturdy, but can’t find much about it. Most ABUS locks are not liked by the Lock Picking Lawyer so I’m not sure what to buy anymore haha.
It’s for an expensive bike, but since I care about weight and it’s stored at home or at work mostly I don’t want to carry 4kg of locks with me.
I wouldn’t recommend either the Abus Combiflex or the Hiplok Lite. They’re not secure enough.
The other locks you’re considering are all good. But you have a range of sizes there.
Do you have quick release levers on your wheels?
If you’re only parking the bike for a couple a minutes then that’s not a high risk situation.
Do you use bike stands to lock the bike? In which case a small u-lock should be fine. Or do you need more flexibility?
My default recommendation will always be the Abus Granit X-Plus 540.
It’s very secure. It comes with a decent frame mount. And it’s big enough to give you plenty of locking options.
It’s heavier than you wanted (1.45 kg). But it’s light for its security level and size.
Thanks for the response! I do have QR on my bike, but I don’t think that’s a concern (although I do have to keep it in mind obviously). Actually since I currently have a frame lock I never tie it to anything. I just park it and lock the lock. So people can obviously easily pick up my bike haha.
I honestly don’t know what kind of flexibility I would need though! I never really used any other locks on a daily use.
The Abus Granit X Plus 540 sounds good, albeit a bit heavy, but it’s nice that it’s ART rated, so my insurance would still be valid. I really like the looks of the Seatylock Mason, but it seems to be a little difficult to purchase here in The Netherlands. The Kryptonite Messenger Mini looks nice, but looks like it might be a bit difficult to bring around with me. Any idea if the FOLDYLOCK Compact is any good? Looks great for carrying it with me.
But I guess if I can get the lock around my frame and rear wheel (when there’s nothing to attach it to) or my frame and a stand or whatever I should be good enough in terms of safety for the few minutes that I’m gone.
I’m a bit confused by what you mean by “bring around with me” and “carrying with me”.
Are you talking about what you do with the lock while you’re riding the bike?
If so then yes, I don’t think the Messenger Mini comes with a frame mount.
It’s so small and light though you can easily thread it through a belt loop on your trousers if you don’t have a bag!
The Foldylock Compact would also be a great choice for short stops!
Both the Foldylock and the Mason should be available on Amazon or through the seatylock website.
You definitely shouldn’t buy a lock that invalidates your insurance! Does your insurance have a minimum ART rating?
Sorry, I indeed mean to bring the lock with me when I’m riding. I usually bring a bag when I’m to work, but not when I’m out on a regular trip. I never bike with trousers, so I must have some kind of frame mount.
I’ll have a look for the Foldylock and Mason and see which is easier to get and have frame mount of some kind.
I’m not 100% sure, but I believe it should be ART1 or 2 at least. Unfortunately the Foldylock and Seatylock both don’t seem to be ART certified, although they still are interesting for me!
Folding locks are definitely the easiest to carry.
I feel like the Abus Bordo GRANIT X Plus 6500 might be a good choice for you.
It’s Sold Secure Gold and Art 2/5 so it’s pretty secure and you won’t invalidate your insurance.
It’s very easy to carry: the frame mount screws into your water bottle carrier holes and since it sits so close to your frame it’s less likely to move about than a u-lock.
The only thing is, it’s a bit heavier: 1.58 kg.
Cheers for the answer again! I bought the Kryptonite Evolution Mini-7 with extender cable because it was on sale and easy to buy over here and it’s kinda light. Would’ve had it yesterday but the delivery is slower because of COVID-19. Anyway, if I don’t like it I will surely look for the Bordo! Looks like a great little package when folded in!
Thanks again for your help!
No worries: that’s a great lock too!
We have just bought a Brompton folding bike for our daughter for becoming a doctor in London. She will be using it to commute to the hospital where she will be working. She will have to leave the bike in the rack outside the hospital, and as it is a very pretty bike, I am a bit worried it will attract attention. Firstly, I was wondering whether she should fold the bike up and then secure it, or leave it unfolded. I thought she could leave a 1m Pragmasis Protector chain at the bike rack and carry say the Kryptonite New York Fahgettaboudit Mini U-lock as a second lock. However, I’m not sure where she should attach each to the bike, or if the Mini U-lock would even be big enough to go round the bike and the rack post. Any suggestions would be gratefully received.
Is there no way your daughter could bring the bike into the hospital grounds at least? It has to go in the street?
If it’s got to be in the street, then you’ll need a really secure lock for sure!
First of all, yes I’d recommend that she locks it folded up. As this will enable her to lock it up with a tighter fit.
Leaving a heavy chain at the bike rack might work. It depends how busy the rack gets…
She could arrive and there’s no space and then she’d need to remove the chain and carry it around looking for a another rack. Thieves (or idiots) may also sabotage the lock.
You could also (as you say) think about a u-lock. I think the Fahgettaboudit is too small. The Abus Granit X Plus 540 is still very secure and is mountable on the frame.
You’ll need to check it’s long enough to go round the rack and the folded up bike. If it’s not, then they do a longer (30 cm) version.
There’s a photo at the bottom of this article of how it might work…
With the right lock (like the Abus) this is pretty secure.
It’s annoying that she can’t take the Brompton into the hospital though!
I hope this helps!
Loved the part about different options to carry a U-lock. Any way to do a more in depth review of options to carry U locks. Maybe other stand alone carriers.
Thanks Troy. I’m working on something right now!
At first, I thought this Abus u-lock was too large and intended to return it. That is until I tried it. The length makes it simple to secure in a variety of locations. I wouldn’t trade it now for a shorter-length lock. The bike I have is an Aventon Pace 500, which weighs around 50 pounds and is difficult to get into a lockable position. The longer length has been so helpful, especially since I do some Uber eats and need to be able to lock up and unlock quickly.
Yeah, for sure, with an e-bike you generally need a bigger lock. I’m glad you’ve found one that works for you Patrick!
Yes, thank you for recommending them. Abus is one of my favorite locks.
What I really want is a Kryptonite New York Compact U-Lock, i.e. a New York, 16mm shackle, 7″ U-Lock.
Unfortunately you can go bigger or smaller in the New York range, or get the less secure Evo Mini-7 – seems you can’t have it all.
Yes there does seem to be space for another small lock in-between the 18mm Fahgettaboudit and the 13mm Evolution Minis!