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The Best Chain Lock (and how to use it!)

Chain locks are made up of a series of hardened steel links (usually inside a protective nylon sleeve) and a lock. The lock can be integrated into the chain, or it can be a separate padlock.

There are several great things about chain locks:

First of all, their relative length and flexibility means you can secure your bike to a wide range of objects.

Secondly, they can be carried relatively easily wrapped around your seat post, so you don't have to deal with any of those annoying u-lock frame mounts!

Chain lock around seat post

Chains: easy to carry around your seat post

And finally they are more resistant to some of the common methods of attack used on other bike locks. For example they can't be bottled jacked or leveraged open. And they're more difficult to cut with power tools. 

However, these advantages come at a significant cost: they are very heavy. Chain locks are far, far heavier than u-locks offering equivalent levels of security.

Because of this, we need to divide chain locks into two groups:

  1. those that are light enough to carry around everyday on your bicycle
  2. those that are so heavy you need to leave them permanently in one place.

So before you buy a chain lock, you should decide what you're really after: portable or stationary security? And once that's established we can find the best chain lock for you.

Don't worry, we'll cover it all here...

Let's start with the qualities that are common to both groups and the things we should be looking out for when buying a chain lock.

The Chain

Not all chains are made from the same type of metal. For reliable security, the links of the chain should be made from a high quality, core hardened steel alloy, that's not too brittle.

The easiest way to guarantee this is to buy from a reputable brand such as Kryptonite, OnGuard, Abus or Pragmasis.

Chain links usually have rounded edges. However, some security chains now have hexagonal or square links.

These are supposed to be more difficult for bolt cutters to grip and spread the cropping pressure over a larger surface. So they're supposed to be harder to crop...

Hexagonal chain links

Hexagonal chain links: are not more secure...

Round chain links

... than round chain links

However, used bolt cutters will have nicks in the blades which can catch the edges of such links, actually making it easier to get a good grip. So in fact, these different shaped links offer no more protection than round links. Indeed they may be easier to crop!

But obviously the thicker the links, the tougher the chain lock...

Chain Link Thickness

Can be cut by bolt cutters?

< 13 mm

Yes (medium size)

13 - 15 mm

Yes (only biggest 36 and 42")

16 mm and above

No

Links with diameters less than 10 mm can be cut relatively easily with medium sized bolt cutters if the thief can get the chain in a good position.

Links with diameters of between 10 and 12 mm can sometimes be cut by medium size bolt cutters if the thief knows what they are doing and can get good leverage on the chain.

Whereas links with diameters between 13 and 15 mm can only be cut by the very biggest 42" bolt cutters which most bike thieves will not have.

And at 16 mm and above the links can’t be cut by even the biggest hand operated bolt cutters.

Different chain link sizes

16 mm chain links are really big and heavy!

But whatever it's thickness, the chance of your chain being cropped can be significantly reduced by keeping the chain as far off the ground as possible when you lock your bike.

In order to crop a decent chain, the thief will need to use one arm of the bolt cutter against the ground as leverage. The further your lock is off the ground, the more difficult and less effective this will be.

The Lock

Any bike lock is only as strong as it’s weakest point. So there’s no point having a super thick, super strong chain if you’re securing it with a cheap, feeble padlock!

Chain locks usually come with their own locking mechanisms. Sometimes they're padlocks or mini u-locks. Sometimes they're permanently integrated into one one end of the chain.

Either way, the locking mechanism should be reliable and should resist leverage attacks, picking, pulling and drilling.

Kryptonite New York disc lock

Shackle should be at least as thick as chain or...

OnGuard Beast padlock

... shrouded so it can't be cropped

If there’s a shackle, it should be as thick as (or thicker than) the chain links or inaccessible to bolt cutters (shrouded).

Chain Lock Length vs Weight

One of the advantages of chain locks (over u-locks) is that their (generally) greater length gives you a wider range of objects to secure your bike to.

However, the longer the lock, the greater the overall weight. And chain locks get very heavy, very quickly.

Even the lighter chains are often too heavy to carry comfortably in a bag on your back. It's true: they can easily be attached to your luggage rack, carried in your basket or wrapped around your seat post.

However, in order to minimize the extra weight, you should generally choose the shortest length that enables you to lock your bike where and how you want to.

Be careful though, some of the short ones are really short! Before you commit to buying a chain lock, measure out a length of rope and test that it's long enough to use wherever you normally lock your bike.

Having said all this, you will just have to accept that a chain lock is always going to be heavier than a u-lock that provides equivalent protection...

Kryptonite Kryptolok Chain Lock

Kryptonite KryptoLok Series 2 955 Mini

Length:

21.5" (55 cm)

Weight:

3.90 lb (1.77 kg)

Security rating:

6/10

Kryptonite Kryptolok U-Lock

Internal Space:

21.5" (55 cm)

Weight:

2.85 lb (1.29 kg)

Security rating:

6/10

For example, the Kryptonite Kryptolock Series 2 u-lock weighs 2.85 lb (1.29 Kg). The lightest Kryptolock Series 2 chain lock is 3.90 lbs (1.77 Kg), nearly a whole pound and 30% heavier.

And at just 21.5” (55 cm) in length, it’s hardly going to give you loads more options when looking for places to lock your bike.

A more practical 37.5” (95 cm) Krytolock Series 2 chain lock is available, but at 5.55 lbs (2.52 Kg) it weighs almost twice as much as the u-lock.

Chain locks are heavy! If that's a problem, get a u-lock or a folding lock.

How to choose the best chain lock for you!

I imagine that you already know whether you want a mobile or stationary lock. It's a pretty clear distinction...

You'll use a mobile chain lock every day, carrying it around on your bike and securing it around your bike and the various street furniture in your neighborhood.

Whereas a stationary chain lock will be left at home (or wherever you leave your bike overnight) and only used there to secure your bike (or more likely several bikes) over longer periods of time.

But what if you want both? Do you want a chain lock that you can carry around every day and use at home overnight? Well, there are locks that can do both. But they don't do either really well.

A two lock system (where you have one for daily use in the street and another that you keep at home for overnight protection) is usually the most secure and practical option.

But we'll cover them all...

Choosing a portable chain lock

How secure should your chain lock be?

The best way to know security level of any bike lock, is to check the ratings from the independent testing house Sold Secure.

If you want to know more about Sold Secure and why they provide the best measure of bike lock security, check out my guide to choosing the best bike lock.

All you need to know here is that Sold Secure test and measure bike locks according to their security level, rating each one Bronze (least secure), Silver, Gold or Diamond (most secure).

But how can you know which Sold Secure rating you need? Well, the best way to find out, is to answer the 3 quick questions in the quiz below…

(The quiz above is new! If you have any problems with it, please send me a message to let me know. Thanks.)

Based on your answers to the three questions, the quiz should recommend either Silver, Gold or Diamond rated bike locks . Bronze locks aren't secure enough for any circumstances, so I don't recommend them at all!

There's quite a bit of variation in security within each rating. So some Silver rated locks are more secure than other Silver rated locks. And likewise for Gold and Diamond rated locks.

With chain locks this will largely be determined by the link thickness. By choosing a thicker Silver (or Gold, or Diamond) chain link, you'll generally be choosing a more secure one.

How long should your chain lock be?

One reason to choose a chain lock (over a u-lock) is the extra options it gives you when you're looking for somewhere to lock your bike. More flexible and longer chain locks go places u-locks can't.

And the longer the chain lock, the more options you'll have. But longer chains are very heavy (as well as expensive).

So get the shortest length that you need to secure your bike. You can use a length of rope to work that out if necessary.

But how should you secure your bike with a portable chain lock? I'd recommend that you don't use a chain lock to secure your frame and your wheels.

If you only use it to secure your frame (tightly wrapped around your top tube), you can keep the chain shorter (and lighter). And even more significantly: it will be further from the ground so it will be much harder for a thief to crop it.

There are plenty of other ways to secure your wheels! And I've written lot's more about how to lock your bike properly.

How will you carry your chain lock around?

Chains locks are best carried wrapped around your seat post (although some brands sell bags that you strap to your frame).

Make sure you've thought about this before you buy one. Is there room on your seat post? If not, is there room in your bag or your panniers?

6 mm chain locks

I wouldn't usually recommend 6 mm chain locks under any circumstances. They can be cropped or cut far too easily.

And I've never seen a 6 mm chain lock with more than a Sold Secure Bronze rating, which is just not good enough to protect our bikes!

However there is one very unusual exception. The tex-lock is a 6 mm chain, encased in a thick textile cover, which makes it look and feel more like a length of rope than a chain lock!

Tex-lock eyelet with X-lock

Combined with the X-lock the Tex-lock is very versatile!

The textile layer provides enough additional protection to have won the chain a Silver rating from Sold Secure. And if you pair it with their Gold rated X-lock, you get a very versatile bike lock...

In high risk circumstances, you can use the X-lock to secure your frame and the chain to protect your wheels. In lower risk circumstances, you can use the chain to secure the frame, (and the X-lock to protect one wheel), with the extra length giving you loads of locking options!

Header

Model

Length

Weight

Security Ratings

Tex-lock S Eyelet and X-lock

31.5"

(80 cm)

3.13 lb

(1.42 kg)

Tex-lock M Eyelet and X-lock

47.2"

(120 cm)

3.73 lb

(1.69 kg)

Tex-lock L Eyelet and X-lock

63.0"

(160 cm)

4.28 lb

(1.94 kg)

But be careful...

You need to understand the different security levels of the different parts of this chain lock (and how to use them properly) to get the best out of it, so check out my full tex-lock review here! And read how it even made my best lightweight bike lock list!

7 mm chain locks

7 mm chain locks are at the very lowest end of what's acceptable protection for your bike. But the Kryptonite Keeper is probably the best of the bunch, with a Silver rating from Sold Secure...

Click on the links in the table to check the prices at Amazon (or other retailers).

Header

Model

Length

Weight

Security Ratings

21.5"
(55 cm)

2.06 lb

(0.93 kg)

Sold Secure Silver

33.5"

(85 cm)

3.50 lb

(1.59 kg)

Sold Secure Silver

47.3"

(120 cm)

3.75 lb

(1.70 kg)

Sold Secure Silver

If your circumstances are low risk, then you might be able to get away with a 7 mm chain lock. Just don't leave your bike unattended for long periods and be careful with you locking technique..

I strongly advise that you don't use a 7mm chain lock to secure your wheels. This will leave it too near the ground where thieves can leverage a pair of bolt croppers to cut it relatively easily.

Instead wrap the chain lock tightly around your top tube and whatever your locking the bike to. This will keep the lock away from the ground and make it impossible for a thief to move it closer.

I think this chain lock could still be cropped without using the ground if the thief has big enough bolt cutters and enough strength. But many bike thieves won't!

What about your wheels? Well, if you're using a 7 mm chain lock, I'd imagine that neither your bike nor your wheels are particularly expensive or desirable.

So you may be able to get away with simply swapping out the quick release levers for standard bolts. Otherwise, there are plenty of alternative ways to protect your wheels that won't put the whole bike at risk. 

8 mm chain locks

They're only 1 mm thicker than the 7 mm chains and although this makes them a fair bit more secure, they still only get a Silver rating from Sold Secure...

Click on the links in the table to check the prices at Amazon (or other retailers).

Header

Model

Length

Weight

Security Ratings

23.6 "

(60 cm)

2.87 lb

(1.3 kg)

Sold Secure Silver

33.5"
(85 cm)

3.86 lb

(1.75 kg)

Sold Secure Silver
Hiplok v1.50

33.5"
(85 cm)

4.08 lb
(1.85 kg)

Sold Secure Silver

33.5"
(85 cm)

4.26 lb
(1.934 kg)

Sold Secure Silver

35.43 "

(90 cm)

3.75 lb

(1.7 kg)

Sold Secure Silver
Squire Mako Combi CN8 900

35.4 "
(90 cm)

3.73 lb
(1.69 kg)

Sold Secure Silver

43"
(110 cm)

5.5 lb
(2.497 kg)

Sold Secure Silver

43"
(110 cm)

5.62 lb
(2.55 kg)

Sold Secure Silver

55"
(140 cm)

6.17 lb
(2.8 kg)

Sold Secure Silver

Abus Steel-O-Chain 9808/170

67"
(170 cm)

7.08 lb
(3.21 kg)

Sold Secure Silver

My favorite is the Hiplok Original [Amazon] chain lock It's got the best weight to length ratio. This means it's much lighter than similarly sized, (or even smaller) chains.

Plus it comes with an integrated Velcro strap which allows it to be worn around your waist like a belt!

Hiploks can be worn like a belt!

Hiploks can be worn like a belt!

This is a really convenient way to carry your chain lock around. It's quick and easy to get it on. And the way the weight is distributed means you'll barely notice it's there. 

But it's worth noting that the weight of these locks is becoming significant. The lightest 85 cm Abus chain lock in the table above, is already heavier than many Sold Secure Gold rated standard size u-locks!

Again, with 8 mm chains, I recommend that you secure your bike by wrapping the lock tightly around your top tube, so it can't be maneuvered close to the floor where it's susceptible to bolt cropper attacks.

9 mm chain locks

At 9 mm, the chain locks start to get significantly more secure. We see several with Sold Secure Gold ratings. 

However, be aware that the Gold rating is usually accompanied by a 2/5 rating from ART which puts these locks at the lower end of the Gold scale.

Click on the links in the table to check the prices at Amazon (or other retailers).

Header

Model

Length

Weight

Security Ratings

Kryptonite KryptoLok Series 2 915

21.5"
(55 cm)

3.90 lb

(1.77 kg)

Abus Granit CityChain X-Plus 1060/140

33.5"
(85 cm)

4.4 lb
(1.95 kg)

Sold Secure Gold
Kryptonite KryptoLok Series 2 915

37.5"
(95 cm)

5.55 lb
(2.52 kg)

Abus Granit CityChain X-Plus 1060/140

43"
(110 cm)

5.29 lb
(2.40 kg)

Sold Secure Gold
Kryptonite Kryptolok Chain Combo

35.5"

(90 cm)

5.85 lb

(2.65 kg)

Sold Secure Gold
Abus Granit CityChain X-Plus 1060/140

55"
(140 cm)

6.04 lb
(2.74 kg)

Sold Secure Gold
Kryptonite Kryptolok Chain Combo
Cell
Cell
Sold Secure Gold
Kryptonite KryptoLok Series 2 915

59"
(150 cm)

8.10 lb
(3.67 kg)

Abus Granit CityChain X-Plus 1060/140

Abus CityChain
1010/170

67"
(170 cm)

7.45 lb
(3.38 kg)

Sold Secure Gold

There's not a huge amount of difference between the Kryptonite Kryptolok Series 2 [Amazon] chain lock and the Abus City Chain 1010 [Amazon] to be honest. 

Both feature integrated locks (as most chains < 12 mm do). They're both rated Sold Secure Gold. But both offer good mid level security rather than high security (see the 2/5 from ART).

However the Abus chains have better weight to length ratios (they're lighter than the Kryptonite chains). While the Kryptonite chain locks will usually be cheaper!

Kryptonite Krptolock Series 2 955 Mini best mid-security chain

Kryptonite Kryptolok: a sensible mid-security choice

The Kryptonite chain locks are also eligible for an optional anti-theft protection, for bikes worth up to $1,500 / £800.

They both come in a variety of lengths. But I recommend you go for the shorter chains and wrap them tightly around your top tube rather than using longer chains to secure your wheels as well.

As already mentioned this keeps them away from the floor where they're more at risk of being cut with bolt croppers. And have no doubt: a 9 mm chain lock is definitely croppable!

Now don't forget: 9 mm locks are heavy! You can of course wrap them round your seat post. But both Kryptonite and Abus sell carry cases and bags that allow you to strap them to your frame.

Since these cases keep the chains close to the frame, they should be more successful than most u-lock frame brackets (where the offset centre of gravity makes them unstable).

But check out the weights before you buy. Because people can be very surprised when they receive their chain lock and feel the weight in their hands for the first time!

Read my full, hands-on review of the Kryptonite Kryptolok Series 2 955 Mini chain lock.

10 mm chain locks

At 10 mm, we're starting to reach the limit of portable security. For sure: the shorter chains can be used as daily bike locks on the move. But they're very heavy...

Click on the links in the table to check the prices at Amazon (or other retailers).

Header

Model

Length

Weight

Security Ratings

Kryptonite Evolution series 4 1016

21.5"
(55 cm)

4.40 lb
(2.00 kg)

Abus Granit CityChain X-Plus 1060/140

Abus Granit CityChain
X-Plus 1060/85

33.5"
(85 cm)

4.63 lb
(2.1 kg)

Hiplok Gold

33.5"
(85 cm)

4.85 lb
(2.2 kg)

Sold Secure Gold
Seatylock Viking 90

35.4"
(90 cm)

5.3 lb
(2.4 kg)

Sold Secure Gold
Kryptonite Evolution series 4 1016

36"
(90 cm)

6.10 lb
(2.77 kg)

Abus Granit CityChain X-Plus 1060/140

43"
(110 cm)

5.84 lb
(2.65 kg)

OnGuard 8021 Mastiff

43"
(110 cm)

5.95 lb
(2.70 kg)

Sold Secure Bronze
Seatylock Viking 110

43.3"
(110 cm)

6.2 lb
(2.8 kg)

Sold Secure Gold
OnGuard 8019L Mastiff

43"
(110 cm)

6.39 lb
(2.9 kg)

Sold Secure Gold
Abus Granit CityChain X-Plus 1060/140

55"
(140 cm)

7.19 lb
(3.26 kg)

ART 3 Stars
Seatylock Viking 140

55"
(140 cm)

7.50 lb
(3.40 kg)

Sold Secure Gold
Kryptonite Evolution series 4 1016

63"
(160 cm)

9.70 lb
(4.40 kg)

Abus Granit CityChain X-Plus 1060/140

67"
(170 cm)

8.27 lb
(3.75 kg)

ART 3 Stars
OnGuard 8021 Mastiff

72"
(183 cm)

8.38 lb
(3.8 kg)

Sold Secure Bronze
OnGuard 8019L Mastiff

72"
(183 cm)

9.28 lb
(4.21 kg)

Sold Secure Gold

The shortest (and lightest) 10 mm chain lock in the table above (the Kryptonite 1055 Mini) is almost as heavy as the 18 mm Kryptonite New York Fahgettaboudit Mini (one of the heaviest u-locks).

And that's a lot of weight to be carrying around every day.

However these locks are also very secure. With two exceptions, they're all Sold Secure Gold. And 3/5 from ART put them at the higher end of that Gold rating.

They're still croppable though! If a thief has a large set of bolt croppers and can use the ground for leverage, they can definitely cut this chain lock.

So I would still recommend you keep the 10 mm chains tightly wrapped around your top tube when locking your bike. And use one of the alternative ways to secure your wheels.

Again, the Hiplok [Amazon] is a good choice here. It an be worn around the waist like a belt so it's easier to carry than the other options.

Hiplok Gold around waist

Hiplok Gold: 12 mm but still easily portable!

Be aware though, it's still heavy: the weight is equivalent to carrying 6 cans of coke around your waist! Read my full, hands-on review of the Hiplok Gold bike chain lock.

What about the other 10 mm chains?

The Kryptonite chains are eligible for optional anti-theft protection for bikes worth up to $2,250 / £1000. And Kryptonite's Key Safe program will replace lost or broken keys.

Kryptonite Evolution Series 4 1055

Evolution Series 4: The LockPickingLaywer's lock of choice!

There's no anti theft protection with Abus locks but they do come with a code card for additional or replacement keys.

Abus Granit CityChain x-Plus

Granit CityChain X-Plus: good weight to security ratio

And for me, the choice would be between the Hiplok, Kryptonite or Abus chains, because the OnGuard 10 mm chains are strange prospect...

The 8020 and 8021 Mastiff are two different lengths of the same chain (featuring an integrated lock). And despite the beefy 10 mm chains, both locks are only rated Sold Secure Bronze!

This makes them low security. I wouldn't recommend any bike locks that have a Bronze rating, let alone heavy 10 mm chain locks that cost a fair bit of money and weigh a ton! I write about this more in my review of the OnGuard Mastiff 8020.

OnGuard Mastiff 8020

A 10 mm chain with a Sold Secure Bronze rating?!

But the bottom line is: avoid the OnGuard Mastiff 8020 and 8021!

By contrast, there's nothing wrong with the security levels of the OnGuard 8019 or 8019L Mastiff. They're both Sold Secure Gold.

But they feature separate padlocks. And I think for mobile security, where you might be locking and unlocking several times a day in busy bike racks, an integrated lock is more convenient.

It's simply quicker and easier to secure your bike when the lock is integrated into the chain rather than separate.

So, if you favour portability, definitely go for the Hiplok Gold [Amazon], as it's by far the easiest chain lock to carry around. Because of the separate padlock, it will take a little longer to lock your bike though.

So if you favour locking speed, then go for either the Kryptonite Evolution Series 4 1055 Mini [Amazon] or the Abus Granit CityChain X-Plus 1060/85 [Amazon] as their integrated locks speed things up a bit.

If you want to know more, you can read my reviews of the Hiplok Gold chain lock and Kryptonite Evolution chain lock.

A chain lock for the street and the home?

These locks can arguably be used for stationary as well as mobile security. But I'd say that in order to be portable they need to be short. And if they're short they're difficult to use at home.

So if that's what your after, proceed with caution...

12 mm chain locks

At 12 mm we are definitely at the limit of what can be used daily as mobile security. These locks are big and heavy...

Click on the links in the table to check the prices at Amazon (or other retailers).

Header

Model

Length

Weight

Security Ratings

Kryptonite New York Noose 1275

30"
(75 cm)

6.95 lb
(3.15 kg)

Kryptonite New York Chain 1217

39"
(100 cm)

8.65 lb
(3.92 kg)

Abus GRANIT Extreme Plus 59/12HKS170

Abus Granit Extreme Plus 59/110

43"
(110 cm)

8.82 lb
(4 kg)

ART 4 Stars
OnGuard 8018 Beast

43"
(110 cm)

9.2 lb
(4.17 kg)

Cell
Kryptonite New York Noose 1275

51"
(130 cm)

10.55 lb
(4.79 kg)

Abus GRANIT Extreme Plus 59/12HKS170

55"
(140 cm)

10.36 lb
(4.7 kg)

ART 4 Stars
Hiplok Homie

60"
(150 cm)

9.48 lb
(4.3 kg)

Sold Secure Gold
Abus GRANIT Extreme Plus 59/12HKS170

67"
(170 cm)

12.57 lb
(5.7 kg)

ART 4 Stars
Kryptonite New York Chain 1217

67"
(170 cm)

13.15 lb
(5.96 kg)

OnGuard 8018 Beast

72"
(183 cm)

13.7 lbs
(6.2 kg)

Cell

However, they also provide a very high level of security. Take a look at the security ratings. Not only are they nearly all Sold Secure Gold, all those rated by ART receive 4/5.

This makes them more secure than all but the most extreme u-locks.

However it does not mean they cant be cropped! A thief using a pair of 42" bolt croppers and the ground for leverage may well be able to cut all of these chain locks.

So again, even with these thick chains: keep them as far from the ground as possible. Personally I'd still recommend you keep them wrapped around the top tube.

But with a 12 mm chain you don't have to be quite so careful. There aren't too many thieves that would have the right croppers, the necessary skill and enough weight(!) to cut a 12 mm chain lock.

The Kryptonite New York Noose [Amazon] is definitely the best 12 mm chain lock. There's a large, circular link at one end of the chain. And by threading the other end of the chain through the circular link, you create a noose which can be tightened around whatever you're locking your bike to.

Kryptonite New York Noose 1275 strongest portable chain

The noose system gives you more length

Why is this so great? Well, it almost doubles the practical length of the chain lock, which means you don’t need to buy such a long one, saving you both bulk and weight!

It also makes it more useful at home as a stationary lock, where usually you'll need a bit more length to work with.

I explain all this in more detail in my review of the Kryptonite new York Noose 1275 chain lock.

Since even the shortest 12 mm locks are right on the limit of what is portable, the longer locks are best used for stationary security at home (or wherever you leave your bike overnight).

In fact, the Hiplok Homie [Amazon] chain lock is specifically designed with home use in mind. It's a nice 60" (150 cm) in length which allows you to secure several bikes at once.

Hiplok Homie comes with a wall hook

The Hiplok Homie: has a hook to hang it on the wall when not in use

And it comes with an integrated hook so you can hang it on the wall when you're not using it!

What about the other options in this list?

The Abus Granit Extreme Plus chain lock is actually classed as a motorcycle lock by Abus, who give it their maximum 20/20 in house security rating. It features an integrated lock for ease of use.

The Kryptonite New York chain lock comes with a separate disc lock that has a 14 mm, double locking shackle. And optional anti-theft protection covers bikes worth up to $3,500 / £1300.

The Beast 8017 (and 8018) from OnGuard also uses a separate padlock with a 11 mm, double locking shackle. And the shackle is shrouded so it's impossible to crop when it's being used with the chain (due to it being inaccessible).

These OnGuard locks haven't been rated by Sold Secure or ART. But don't worry about that (unless your insurance policy stipulates a Gold rated lock)...

It's not that these two locks aren't secure. It's that they haven't been submitted for rating. Have no doubt: these OnGuard chains are very secure locks!

Any of these 12 mm locks will offer great high security protection at home or on the move if used correctly. But if you're going to use them as mobile protection, please check you're OK with the weight first!

Choosing a stationary chain lock

If we're choosing a chain lock to leave at home (or wherever we leave our bikes overnight), we don't need to worry about the "risk level" questions...

Over 50% of stolen bikes are taken from the owners home. So your bike is actually more at risk at home than it is when it's locked on the street.

With that in mind, my advice is: get the most secure bike lock you can afford. And this means the thickest chain lock you can afford.

And the great thing is: we don't have to worry about how we're going to carry it around!

14 mm chain locks

When we get to 14 mm chains, we’re no longer talking about mobile security. These are not locks that you take with you to the shops.

Their bulk and weight mean that generally you leave them wherever you lock your bike overnight.

Click on the links in the table to check the prices at Amazon (or other retailers).

Header

Model

Length

Weight

Security Ratings

Kryptonite New York Fahgettaboudit Chain 1415

39"
(100 cm)

10.80 lb
(4.90 kg)

OnGuard 8016L Beast

43"
(110 cm)

14.8 lb
(6.71 kg)

Cell
Kryptonite New York Fahgettaboudit Chain 1415

60"
(150 cm)

15.25 lb
(6.92 kg)

OnGuard 8016L Beast

72"
(183 cm)

22 lb
(9.98 kg)

Cell

However a 14 mm chain lock could be taken out with you occasionally if you're visiting a particularly high risk area or you'll be leaving your bike unattended for a long period.

These locks are very secure indeed. The Kryptonite New York Fahgettaboudit not only has Gold rating from Sold Secure. It also has a Motorcycle Gold which is an even more demanding rating.

That's not say they can't be cropped though. They can. 14 mm chains can conceivably be cut by the very biggest bolt cutters. But it takes a experienced thief, of considerable weight who is also able to get the chain in the right position.

So again I'll say: keep you chain as far from the floor as possible. In a bike shed or garage this might mean installing a wall anchor rather than a floor anchor to use with the chain lock.

There's not a lot to choose between the Kryptonite and OnGuard chains here. They're both great locks!

OnGuard Beast 8017

OnGuard Beast: very secure and usually cheap!

With Kryptonite's New York Fahgettaboudit chains you get a 15 mm double locking shackle, the maximum 10/10 in house security rating, and both Motorcycle and Bicycle Gold ratings from Sold Secure. Plus optional anti-theft protection which covers bikes worth up to $3,750 / £2000.

With OnGuards Beast chains you get a 14 mm, quadruple locking shackle, a maximum 99/100 in house security rating and optional anti-theft protection for bikes worth up to $5001.

Again, OnGuards locks aren't rated by Sold Secure simply because they haven't been submitted.

Usually an OnGuard chain lock will be significantly cheaper [Amazon] than those from Kryptonite [Amazon]. However they're not as pick resistant and the after sales care and anti-theft protection isn't as reliable.

15 mm chain locks

There's only one widely available 15 mm chain lock. And that's the very  impressive Kryptonite New York Legend...

Click on the links in the table to check the prices at Amazon (or other retailers).

Header

Model

Length

Weight

Security Ratings

Kryptonite New York Legend Chain 1515

36"
(90 cm)

9.50 lb
(4.31 kg)

ART 4 Stars
Kryptonite New York Legend Chain 1515

Kryptonite New York Legend Chain 1515

60"
(150 cm)

15.95 lb
(7.23 kg)

ART 4 Stars

It's still theoretically possible for the right thief in the right position with the biggest bolt cutters to crop this chain lock. But I've never heard of it actually happening!

That ART give it a maximum 5/5 stars says it all really. This is one of the strongest bicycle locks you can buy.

The lock features a 16 mm double locking, shrouded shackle. And optional anti-theft protection covers bikes worth up to $4500 / £2500.

Kryptonite New York Legend 1515 best high-security chain

New York Legend: most secure widely available lock

This is a fantastically secure chain lock for bicycles. In fact, from the three big lock brands, it is probably the most secure bike chain available. Read my full review of the New York Legend.

16 mm chain locks

Finally, at 16 mm, these chains can no longer be cropped by any manual bolt cutters. They can only be defeated by power tools.

Header

Model

Length

Weight

Security Ratings

Almax Immobiliser Series III

28"
(700 cm)

9.15 lb
(4.15 kg)

Pragmasis Protector 16 mm

39"
(100 cm)

12.13 lb
(5.5 kg)

Pragmasis Protector 16 mm

60"
(150 cm)

17.09 lb
(7.75 kg)

Almax Immobiliser Series III

60"
(150 cm)

17.09 lb
(7.75 kg)

Pragmasis Protector 16 mm

79"
(200 cm)

22.05 lb
(10 kg)

Almax Immobiliser Series III

79"
(200 cm)

22.05 lb
(10 kg)

Pragmasis Protector 16 mm

98"
(250 cm)

27 lb
(12.25 kg)

Almax Immobiliser Series III

98"
(250 cm)

27 lb
(12.25 kg)

And they're incredibly heavy. Not only are they completely non-transportable, you’ll also need to be careful they don’t damage your bike just through their weight!

The Protector range from Pragmasis is perhaps the ultimate bicycle chain lock. The 16 mm links are formed from hardened boron steel and are impossible to bolt crop.

It comes with a Squire SS65CS Stronghold Lock which has a shrouded shackle which is also impossible to bolt crop!

Pragmasis Protector 16 mm with Squire lock

16 mm Pragmasis Protector with Squire Stronghold

The only way a thief is going to defeat this lock is with power tools and it will take a long time and make a lot of noise!

Very similar to the Protector range, the Almax Immobiliser Series III is slightly cheaper, (although I’m not sure it’s available in the US). It’s also made from 16 mm hardened boron steel links. And it comes with the same Squire SS65CS Stronghold Lock.

Personally, I'd go for a Pragmasis chain lock because I like their environmental policies. But I appreciate that not everyone can afford to be so picky!

Best Chain Lock Summary

There are two types of bicycle chain lock:

  1. those light enough to carry around on your bike daily
  2. those so heavy they're best used as stationary security

Portable Chain Locks

Portable chains have links that are less than 13 mm thick. And even 12 mm will be too much for many people. They're far heavier than u-locks. But they do have several advantages...

Firstly, because they're relatively long and flexible, you can secure your bike to a wider range of objects.

Secondly, because you can wrap them around your seat post or top bar, they can be easier to transport.

And thirdly they can't be defeated by leverage attacks and are more difficult to cut with an angle grinder (since the links move about when you try to cut them).

However one big disadvantage they have in terms of security is the fact that the < 12 mm links that make up a portable chain lock can be cropped by manual bolt cutters fairly easily (if they're close to the floor).

And this is why, if you choose a chain lock for portable security, I recommend you secure your bike by wrapping the chain tightly around your top tube. 

This will keep it away from the ground and make it very difficult (if not impossible) for a thief to crop a decent portable chain lock.

You'll have to come with a different way to protect your wheels, but there's load of options and at least your bike will be safe!

Please check the weights carefully before you buy though. Even the shortest portable chain lock will be heavy. If weight is big issue then you're probably best off with a u-lock.

The Hiploks have great security to weight ratios. And you've also got the useful option of carrying them around your waist.

For protection in really low risk circumstances, the Kryptonite Keeper chain lock is a good choice. For medium risk, the Kryptonite Kryptoloks or the (even more secure) Abus CityChains are more appropriate.

But if you're circumstances are high risk, then the Kryptonite New York Noose or Gold Hiplok chain lock would be my choice..

Stationary Chain Locks

Stationary chains usually have links that are thicker than 13 mm. And there are several reasons why for immobile, overnight security these are the best option...

First of all: security. They can’t be defeated by bottle jacks or leverage attacks, are more difficult to attack with power tools (like angle grinders) and if the links are thicker than 15 mm they can’t be cropped by any manual bolt cutters.

Indeed 15 and 16 mm chains are the most secure way to lock your bike.

Secondly: practicality. When you're securing a bike at home, in a garage or bike shed, then the best way to that is with a ground (or wall) anchor. And chain locks work far better with anchors than any other type of lock.

And since at home, you might be securing more than one bike at a time, you can get a chain lock that is long enough to go around all of them!

Of course, any bike lock is only as secure as it's weakest link. And this is particularly relevant when we talk about stationary chain locks which may be used in a shed or garage or even with other bike storage ideas.

Make sure that whatever you secure your bike to is as secure as the chain lock. If you don’t have anything appropriate then you should invest in a good ground anchor. And make sure you know how to lock you bike properly.

I hope this page has been useful and that it’s helped you find the best chain lock for your bike. Once you've bought a chain lock, don't forget to clean and lubricate it every few months to stop it jamming.

And if you have any feedback or questions, please let me know below…

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