Kryptonite Evolution Mini-7 (New-U) Review | The Best Bike Lock (2024)

The Kryptonite New-U Evolution Mini 7 [Amazon] is a pretty well known bike lock, if only because it’s been the Wirecutter's “best bike lock” top pick for the last couple of years.

And I think they made a good choice! Because this is a u-lock that’s not too heavy, is pretty secure, and will provide adequate locking opportunities for most people riding in an urban environment.

However, I’ve seen a lot of complaints from cyclists that say that it’s too small to lock their bikes with.

In some cases, this will undoubtedly be true. But in other cases, I suspect that they’re not aware of the different ways you can use a lock like this to effectively secure your bike.

Unboxing the Kryptonite Evolution Mini-7

So I thought I’d write a full review, where I tackle this issue in detail! I’ll also (as always), look at how secure it is, and how easy it is to carry around. And I’ll suggest some fantastic alternatives, if in fact it’s not the best bike lock for you!

So let’s crack on…

How secure is the Kryptonite Evolution Mini-7?

The Kryptonite New-U Evolution Mini 7 has a 13 mm thick shackle, made from Kryptonite’s top of the range “max performance” hardened steel. This is the same steel that’s used on their most secure bike locks.

The Kryptonite Evolution Mini-7 features a 13 mm thick hardened steel shackle

With the introduction of the New-U range, Kryptonite have also made some significant structural changes that improve the security of the Mini-7 (there is a less secure, earlier version).

First of all the shackle has changed from the old bent foot design (which only locks on one side), to a double deadbolt shackle that locks into the cross bar on both sides.

This in itself provides a massive security boost, as it means the shackle must be cut twice (once on each side) to open the lock up. And it also gives extra protection from twisting and leverage attacks that are commonly used to defeat lesser u-locks.

Double locking shackle + scoops and bumps = more security!

They have also made some “scoop” shaped cut outs in the tips of the new shackle. When the shackle is inserted into the crossbar, these scoops slot into corresponding “bumps” in the bottom of the case (the holes for the shackle now extend all the way through the crossbar).

This means that when the Mini-7 (or indeed any of the New-U Evolution u-locks) is locked, the shackle is anchored to the crossbar in four places. By the two deadbolts. And also by the two bumps!

This makes the locked structure of the u-lock much stronger. And it gives further protection from twisting and leverage attacks.

The shackle now passes all the way through the crossbar for extra stability

Having said all that, let’s not get carried away. Wirecutter claim that this lock can’t be cut by bolt cutters. What they mean is: they weren’t able to cut it with their bolt cutters.

A 13 mm thick shackle can be cut by the biggest bolt cutters, if the thief is heavy enough and can get the lock in a favourable position (close to the floor where they can use the ground for leverage and get all their weight on top of the other arm).

Of course, this means that all we have to do is keep it far from the ground and no-one will be able to crop it (more on this later). But it’s worth making the point: this lock is not bolt cutter proof.

Kryptonite themselves give the New-U Mini-7 an in-house security rating of 7/10, which makes it high security but not ultimate security. Sold Secure give it a solid Gold rating. And ART give it a decent 2/5 stars.

The ART rating is the most significant here. A 2/5 star rating makes it a “lock for bicycles” as far as ART are concerned. But they give plenty of bicycle locks 3/5 stars. So what it means to me is that it’s a the lower range of that Gold rating.

So for sure, this is undoubtedly a high security lock for high risk circ*mstances. But let’s not kid ourselves: there a much more secure bike locks out there.

Is the Kryptonite Evolution Mini-7 easy to carry?

One of the best things about smaller u-locks is that they’re easier to carry. This is because they’re both less bulky and lighter. So they take up less space in a bag. Some of them can be hung off a belt clip or even slipped into a pocket!

And if you clip them into a frame mount, because they’re lighter and their centre of gravity is closer to the frame, they’re less likely to rattle, work loose or fall off.

The Kryptonite New-U Evolution Mini-7 u-lock weighs 1086 g (2.39 lb)

The Kryptonite New-U Evolution Mini-7 weighs (with cable) about the same as 4.5 cans of co*ke

This isn’t an insignificant amount of weight to be carrying around every day. So while it slips into a bag very easily, I’m sure many people would prefer other options for carrying it around while they’re riding.

And the Mini-7 (like all Kryptonite u-locks except the Fahgettaboudit Mini) comes with the much maligned FlexFrame-U Bracket, for fastening your u-lock to your bike frame. And I say much maligned because people are always complaining that it doesn’t work very well!

The Kryptonite FlexFrame-U Bracket frame mount

In my experience, the complaints seem a little unfair, and I’m sure many of them have their origins in not reading the instructions properly! Because no-one reads instructions properly. And unlike other frame mounts, it’s not really obvious how to fit it without reading the instructions properly!

Essentially, there are 2 parts to the FlexFrame-U. A belt that attaches to your frame. And a plastic clip, which screws into the belt (and into which the u-lock is slotted).

The belt part of the FlexFrame-U Bracket frame mount

So first you tighten the belt around your frame (after cutting the rubber underlay to size, which is a bit of a pain). However, it never feels like it’s tight enough, which is also annoying. Don’t worry though, cos the next step will actually tighten it up...

You then screw the plastic clip into the metal buckle on the belt. This seems to tighten the belt properly around your frame. And if all goes well, by the end of this step you’ll have a nice strong fit!

The plastic clip part of the FlexFrame-U Bracket frame mount

Using a flexible belt like this probably means that the Kryptonite frame mounts fit a wider variety of frames than the other (easier to understand) frame mounts. And I’ve got to say, personally I’ve never had any problems with it.

I did have to read the instructions though!

Once it’s installed, it seems as stable (but no more so) than most other frame mounts. Except for the Abus ones which I think are the best!

The Kryptonite New-U Evolution Mini-7 finally in the frame mount!

One other thing worth mentioning is that the Mini-7 comes with a 4ft cable lasso, which you’re meant to use in conjunction with the u-lock to secure your other wheel. I’ll talk about this cable (and why I don’t like it) later.

But one of the reasons I don’t like it, is that I find these cables hard to carry. They’re constantly trying to uncoil. And if you don’t have a bag to stick them in, you’ll probably have to Velcro them to your lock.

Strapping the cable lasso to the u-lock

For me at least, it’s a hassle to coil them up, it’s a hassle to Velcro them to the lock. And they never feel completely secure: I’m always worrying about them falling off when I’m riding. Plus they look untidy!

Is the Kryptonite Evolution Mini-7 easy to use?

The mini in the Mini-7 is actually referring to the width of the u-lock. How do I know this? Because Kryptonite also make a Mini-9, which is actually longer than a standard u-lock! While all of the Mini u-locks are just 3.25” (8.3 cm) wide.

Kryptonite New-U Evolution Mini7 dimensions: 7 x 3.25” (14 x 8.3 cm)

So the Kryptonite New-U Evolution Mini-7 measures 7 x 3.25” (14 x 8.3 cm), internally. This makes it a couple of inches shorter, and less than 1 inch narrower, than a standard u-lock. Which is not a big difference.

But it does makes a big difference to how you use the lock in a bike rack.

Most guides recommend securing your bike by passing a lock around the seat tube and the rear wheel. Probably because the seat tube is the strongest part of the frame that’s close to the rear wheel (which is the most valuable of the two wheels)...

The most commonly recommended way to lock a bike: seat tube and rear wheel

So when it's locked like this, a bike looks more secure.

But you won’t be able to lock the vast majority of bicycles like this with the Mini-7. Even on my relatively thin framed and thin wheeled bike, I couldn’t get the Mini-7 around the wheel and the seat tube.

I was unable to get the Mini-7 around my seat tube and rear wheel

Around the seat stays and rear wheel rim is very secure.

But through the spokes and around both seat stays is also very secure

In such cases, an alternative is to keep the lock around the seat stays but avoid the wheel rim, so the lock just goes through the spokes. This may look slightly less secure. But the frame is obviously still protected and there’s actually no way to remove the wheel while the lock’s there.

A similar option (which uses even less lock space), would be the Sheldon Brown technique, where the lock just goes around the wheel rim, but crucially within the rear triangle. Although it may look like only the wheel is secured, it’s impossible to steal the bike without destroying the wheel.

The Sheldon method also protects the frame and rear wheel

But because it is still possible, I’d only recommend this method for short stops. The other issue with this method, is that because it looks steal-able a thief might damage your bike whilst trying and failing to do so.

I was also able to secure the frame and the rear wheel by passing the lock through the chain stays. With a lock that’s vulnerable to bolt cutters (like the Mini-7) though, I’m not so keen on this method as it leaves the lock very close to the ground.

Locking the frame and rear wheel through chain stays: leaves lock too close to the ground

But the point I’m making is that there are lots of ways to safely lock your bike with the Mini-7 if you’re prepared to think beyond the most commonly recommended methods.

Of course we’re talking about locking your bike to a bike rack here. This is very much a bike rack lock! If you live somewhere where you won’t be locking your bike to a bike rack in the vast majority of instances, then the Mini-7 probably isn’t for you!

Using the cable lasso with the Kryptonite Evolution Mini-7

Finally, a quick mention for the 4 ft cable that comes with the Mini-7. It’s designed to be looped through the front wheel and then connected to the u-lock to protect that front wheel.

However, these cables can be snipped through in seconds with the one tool that all bike thieves carry. So they only provide a mild deterrent. There are far more secure ways to protect your wheels (and seat) and I’d urge you to check them out before committing to this method.

Keys and Maintenance

You’ll get three keys with the Kryptonite New-U Evolution Mini-7. And just like all the Evolution locks, one of them has an LED light to help you out in the dark.

You get 3 keys, one with an LED light to help you in the dark

The Mini-7 features a sliding external keyhole cover

I like these external coves as they can’t beak off inside the keyhole! Plus they’re just screwed on. So you can remove them if you need to. And if they get damaged, Kryptonite will send you a new one!

Kryptonite Evolution Mini-7 Review Summary

I think the Mini-7 is a cracking lock and was a great choice from Wirecutter. If you’re prepared to be open minded about your locking technique, it should suit the vast majority of cyclists in an urban environment.

Even chunky wheeled mountain bikes and heavy city bikes that are draped with fenders should be able to use this lock successfully, if they choose the appropriate locking method!

It’s definitely a "bike rack bike lock" though! You’re going to struggle to use it on anywhere else (such as street signs, lampposts railings etc) as it just won’t fit. So if you need more versatility, you should look elsewhere.

The Kryptonite New-U Evolution Mini-7 is a great lock if you only use bike racks!

In terms of security, as long as you keep it well away from the ground, it’s perfectly adequate for the relatively high risk circ*mstances many of us face in big cities and towns.

However, it’s far from the most secure bike lock available, and if your circ*mstances are really high risk, I’d recommend you go for a stronger lock.

Neither is it the lightest bike lock around. And there are plenty of muchmore lightweight options too.

But it will be a nice compromise for many urban riders!

If you have any doubts, I’d suggest you read my guide to finding the best bike lock for you, where you’ll also be able to determine your personal risk level!

Alternatives to the Kryptonite Evolution Mini-7

If the Kryptonite New-U Evolution Mini-7 isn't quite right for you, don't worry. Because there are always lots of alternatives...

Need more locking options?

While both locks are Sold Secure Gold, the Evolution Standard gets 3/5 stars from ART as opposed to the 2 stars the Mini-7 gets.

So if you need more locking options and more security, and you don’t mind about the extra weight and bulk, the New-U Evolution Standard could be a great choice!

Read my full, hands-on review of the Kryptonite New-U Evolution Standard.

Looking for something more secure?

It’s actually nearly 12% heavier than the Mini-7 though. And if you need one, you’ll usually have to buy the frame mount separately. But the Abus frame mounts are the most stable and reliable that I’ve used.

So, if your risk levels are telling you that you need something a bit more secure than the Mini-7, this could be a fantastic choice!

Looking for something cheaper?

You can buy it with or without a complementary cable lasso. And the frame mount is easier to install (although probably not as versatile when it comes to different frame shapes!).

But the best thing about the OnGuard Pitbull Medium? It’s often a good 30% cheaper than the Kryptonite! So if you're looking for a bargain, this could well be the lock for you.