We’ve seen several different solutions to try to create theft-resistant and even tamper-proof bolts to secure the most often stolen parts of a city bike – the wheels and the saddle/seatpost combo. Last fall we got the details on the NutFix system from German lock specialists Abus, which is quite a sneaky solution. Here’s a closer look at how it actually works…
The Nutfix caps replace the standard nuts & bolts that secure your components with a special nut that can only be operated when you rotate the bike 90° onto its side. So, as long as you lock your bike up securely to a fixed rack or object, your components should be there when you return.
Basically, the cap that covers the bolt can’t be lifted until it’s facing straight up (like when you’re bike is lying on its side). So, unless the thief knows to lay your bike down first, and has some pretty specific tools (more on that below), chances are they won’t even know how to or be able to remove the axle or seatpost bolts to steal your parts.
NutFix comes in three varieties:
- Complete quick-release axles kits
- Individual axle nuts for bolt-on wheels
- Seatpost collars
They each come in a variety of sizes to fit many different bikes, and are available now in red, black & silver (the other colors didn’t seem to make it into production.)
The axles can be used for bikes with quick release wheels. They are sold both in pairs for $70 or individually (front or rear) for $35 each. The come in 100mm & 135mm lengths and require a thin 8mm open-ended wrench (like these Duratech ones) or very thin adjustable wrench to remove it once you lay the bike on its side.
The individual axle nuts work with bolt-on wheels (like on many kids bikes from Walmart, etc.), and you only need one NutFix (one side per wheel) to secure each wheel. They are selling for $35 a piece and are available to fit 3/8”, M9 & M10 threaded axles.
To “unlock” it, just drop the bike onto its side and use a narrow 15mm cone wrench, which conveniently is also the most common pedal wrench. The Park Tool PW-5 is perfect for this.
Four different sizes of NutFix SeatPost Collar are also available – 28.6, 30.0, 31.8 & 34.9mm – to fit a wide range of bike likely to serve around town. They are a complete solution of clamp & bolt, so replace the bolt-on or quick-release collar that is already on your bike.
That means they won’t fit every bike, as some have integrated seatpost collars, or use a different size tubing. To see if you can us one on your bike, remove the entire clamp from your bike and measure the diameter of the seattube extension above the toptube.
The black anodized aluminum clamp and colored NutFix setup sells for $45, just be sure to install it straight (the NutFix cap pointing directly to the side) or you may end up fighting the bike to get it leaned properly to loosen it with an 8mm wrench.
Abus NutFix are available in the US & Europe through independent bicycle dealers and on Amazon in select colors.