Abus NutFix Wheel Lock Review

Abus Nutfix set

Abus NutFix Summary
Skewers for Hollow Axle Wheels120 mm
150 mm
Nuts for Solid Axle Wheels9 mm
10 mm
Seatpost Lock28.6 mm
31.8 mm
34.9 mm


We all know that wheel and seat theft is rife. Anyone who leaves their bike outside for long enough will eventually have one or the other stolen. Or both. It’s a real pain!

To try and combat this problem, Abus have come up with a new security system for our wheels and seats called NutFix. I got my hands on a pair of black, quick release 120f/150r wheel skewers to see how they perform in real life!
Abus NutFix boxed

How does it work?

The NutFix system uses gravity. While your bike is upright, the skewers are locked and can’t be unscrewed. Which means that your wheels (or seat) can’t be stolen! It’s only when your bike is tipped onto one side that the locking mechanism is released and you’re able to unscrew them.

This gravity based approach is nothing new. Kryptonite and Zefal already offer wheel and seat skewers that are based on the same principle. But the Abus system works slightly differently. So lets have a look at it in more detail…

Abus NutFix unboxed

For each component you want to secure, there’s a skewer and a nut. So in my box there’s a pair for each of the wheels.

One end of the skewer has a smooth, slanted cap that’s actually part of the skewer and isn’t removable. This is the anchor. It fits very tightly against the wheel drop out and I don’t think there’s any tool that could get a grip of this to turn it.

Abus NutFix skewers

At the other end is a fat, screw-on nut that acts as the locking mechanism. This nut has an central hexagonal section which you grip and turn with a 8 mm spanner to tighten the nut.

The outer case of the nut can be popped over the internal section while the nut is in any position. But it can’t be popped off again unless the nut is vertical.

Abus NutFix nuts

You install the system in the same way as you’d install any other wheel skewer: with the bike either upright or upside down. Simply slip the skewer through the wheel and the drop out…

Abus NutFix anchor on wheel

Then (making sure the internal hexagonal section is sticking out), start to screw the big nut onto the other end of the skewer. Tighten it up by using an 8 mm spanner on the hexagonal section.

Abus NutFix before the case is popped over

When it’s nice and tight, if you push the nut towards the hub, the outer shell will pop over the hexagonal section making it inaccessible…

Abus NutFix after the case is popped over

You can’t pull the shell out again while the bike is upright and if you try to unscrew it, the case just spins freely. Your wheels are now secure!

Brilliant! I found the whole system really easy to install and it took less than five minutes. But just in case you didn’t understand my explanation, here’s a video from Abus themselves…

How secure is it?

Once the hexagonal section that’s used to tighten or loosen the nut is covered, you can’t uncover it again while the bike is upright. It doesn’t matter how much you push or pull, it won’t move. And it since the outer shell is not used to tighten or loosen the nut, it just spins freely if you try to unscrew it.

I had a really good go and breaking into it while the bike was upright and got nowhere. So I think it’s pretty secure in that respect.

If you want to remove the skewers to change a tire or adjust your seat, you need to lay your bike on it’s side so that the skewer and the nut are vertical. When the nut’s in this position the gravity controlled mechanism allows you to pop the case off and you can then unscrew the nut using a spanner on the hexagonal section.

This works really well. There were none of the problems I’ve encountered with other gravity based systems where the release mechanism doesn’t always work smoothly. As you can imagine, that can be incredibly frustrating when you’re trying to fix a puncture!

Abus NutFix on bike stand
This is how I usually lock my bike…

The problem for me is that it’s actually quite difficult to lock your bike so that it can’t be turned on it’s side! If you’re only using one lock on a Sheffield stand, then it doesn’t really matter which part of the bike is secured, it’s usually possible to lift and shift the bike about a bit so that you can get it horizontal enough to pop the case off…

Abus NutFix with bike flat over stand
But I can lift the bike up and horizontal while still locked

For sure, you can make it more difficult with a tighter fitting lock (which would also be more secure in itself). And in a busy bike rack there probably won’t be enough room to maneuver a bike in this way.

But the fact remains that I couldn’t find a way to lock my bike to an empty Sheffield stand, with a standard sized U-lock that prevented me from tipping the bike enough to pop the bolt case off.

So while this system will foil the casual thief who is either unaware of how it works or is unable or unwilling to get the bike on it’s side, a more determined thief may well be able to get your bike in position where he could free the bolt and steal your wheels or seat.

Of course this chance can be reduced by a smaller lock that provides a much tighter fit against the stand. And obviously, if you’re using these skewers, then you won’t need a big U-lock that goes round the frame, the immovable object and the wheel anyway!

But it’s worth bearing in mind that in order for this system to work properly and be fully trustworthy, you have to prevent the bike from being tipped on it’s side.

Wrapping up

All in all, I liked the NutFix system. The components are really well made, they’re easy to install and they function as intended.

I like the fact that you don’t need to carry around any special tools (other than a normal 8 mm spanner) and as long as your bike’s vertical, it seemed very secure.

The fact that there’s no quick release levers and no obvious way to unscrew the nuts will prevent most thieves from even trying to steal your wheels or seat. But in order to stop a more determined thief, you’re going to have to be very careful about the way you lock your bike.

If a thief can get your bike horizontal while it’s locked up, then they could pop off the nut shell and steal your stuff. So to stop them doing this you’ll need a lock that fits very tightly around your bike. My standard sized U-lock was too big, so I’d need to buy a new lock to be absolutely sure.

Having said that, even when it’s possible to get your locked bike into a horizontal position it will rarely be easy. And a thief will look very conspicuous. So I can’t see it being an issue in most cases.

What’s more, anything that reduces the weight of the security systems we have have to carry around every day to protect our bikes should be welcomed. And if the Abus NutFix means you can use one lock rather than two, then that’s something we should celebrate!

There are of course alternatives. Slightly more secure are the likes of Pinhead and Pitlock which provide unique keys to unlock their skewers. Slightly less secure are the non-standard keys of systems like Hublox, Trans-X and ETC.

And of course there are plenty of DIY approaches too. For more details, check my complete guide to protecting your wheels and seat.

Abus NutFix Specs

Abus Nutfix set

Abus NutFix Summary
Skewers for Hollow Axle Wheels120 mm
150 mm
Nuts for Solid Axle Wheels9 mm
10 mm
Seatpost Lock28.6 mm
31.8 mm
34.9 mm