Security chains with padlocks

A heavy motorcycle or bicycle security chain provides a nice combination of toughness and flexibility. It also lets you lock to more distant points that would be impossible to reach using a U-lock.

Ideally, pick a chain with links having a non-circular cross-section. That multi-sided shape supposedly causes a link to slip away from the cutting surface of bolt cutters and other tools.

These chains are often sold with an exceptionally tough lock, but sometimes you can buy just a chain and then use the lock of your choice.

The following are some impressive chains I found on the Web:

In the US, Kryptonite and OnGuard seem to be the most common brands found in bicycle retail outlets. If you want an ABUS chain, you could pick a model from the ABUS website, and then ask a reseller like lockitt.com or a local motorcycle accessory store to order it.

One big problem with chains is that they are very heavy. For example, a 170 cm (5.6 feet) ABUS chain would provide a nice useable length for many locking situations. That chain, with a lock, weighs 3.6 kg (8 pounds) for a bicycle version with 9 mm thick links. An equivalent motorcycle version with 13 mm thick links weighs 5.7 kg (12.5 pounds). You will especially be affected by this weight when biking up a hill. If you always commute to the same location, you could just leave your chain and lock there all the time, perhaps seeking permission first!

Those chains are also expensive, often more than US$100 for a thick chain with a big padlock. They might be worth it to you, even if the chain is worth more money than the bicycle it guards. Losing a bike could force you to disrupt your schedule, take an expensive taxi ride home, spend time reporting the theft, and maybe spend time and money shopping for another bike. If your bikes are stolen repeatedly, then the chain makes even more sense.




The quick and simple way to lock up is to use the chain in a simple loop.


Bicycle security chain around frame, tire, and a post

If you need to stretch your chain a long way to reach a pole, you can lock up handcuff-style. This requires you to be carrying two locks with the chain. At each end of the chain, you would create a little loop using a lock, as shown. One loop could encircle a pole and the other could encircle the frame of your bike.


Bike chained using two locks, like handcuffs

Notice that I had to modify the chain to do this. In the photo of a simple loop, you can see the chain in its original condition. I needed to pull back its black cover from the end, so that a section of chain would be exposed; otherwise, I couldn't use the lock as shown in the previous photograph.

The chain originally had rivets at each end, I guess to prevent the cover from sliding. I used a tough scissor-like hand tool to chew at a rivet's center, seen here in the photo. After a half minute I had done enough damage to break the rivet free. I threw away the rivet parts.


Rivet holding the fabric sleeve over a security chain

I pushed that black sleeve's end toward the middle of the chain. It took a surprisingly large amount of time, effort, and strength to do that. I then cut a section from an old mountain bike inner tube (thin, not thorn resistant) and slipped it over the chain section I had just exposed.


Chain with padlock




You can achieve the handcuff effect with a single lock by using a noose chain.


Noose chain

This one was remarkably inexpensive, probably because it came with a lock that uses a tubular key. This is not necessarily a problem, as I discuss in my page about bad locks. Anyway, you can buy a similar lock by OnGuard or by Kryptonite that uses a flat key, in addition to this chain, and your total cost still would be pretty reasonable. You can get a similar chain made by Kryptonite.

You wrap the chain around the thing you want to trap, then grab that circular ring and slip the chain's other end through the ring.


Noose chain around a pole

The other end of the chain attaches as shown at the bottom of this page, in the last two photos.




Following are some examples of locking with a noose chain.


Noose chain handcuffing bike frame and front wheel to a pole Bike chain loop containing frame, rear wheel, removed front wheel, and a pole

Bike chain handcuffing each wheel to the frame, and trapping a pole between chain and frame Rear wheel, frame, and pole handcuffed at one end of chain, front wheel at other end

Rear wheel and frame handcuffed at one end of chain, front wheel and pole at other end Handcuff frame to pole

Handcuff frame to front wheel where it meets a bicycle parking rack