How do I know which length of security chain I need?

Updated on Oct 12, 2026

Park your bike where you normally leave it, then run a piece of rope through the anchor and the part of the bike you intend to secure. Follow the complete chain route, including bringing the ends together where the lock will sit, then measure the rope.

A thick chain cannot bend as tightly as rope, so allow room to position the links and engage the lock. Choose the shortest available length that works comfortably rather than one that only just reaches.

If you are choosing a noose chain, include the length used to form the noose around the anchor or bike. Do not assume that every metre of chain will be available as straight-line reach.

Check that the actual chain links will fit through the intended openings. Keep the chain and lock off the ground where practical, and leave enough flexibility to cope with small changes in your parking position.

Chain size considerations

Bear in mind that chains are quite bulky and it is often impossible to pass them through the frame of a sports-style motorbike or off-road motorbike, but you must instead go through the swingarm/wheel and/or over the saddle.

A chain and lock should ideally be held off the ground for best security (a lock that is on the ground can be hit with a sledgehammer whereas it will move out of the way if it moves feely in mid-air).

Remember also that a chain looped over the saddle may seem ideal but competent thieves may push the bike over on its side and drag it clear of the chain if it becomes loose - they don't mind damaging part of the bike if they get most of it quickly and easily! If you do loop the chain over the seat - make sure it also goes through a part of the bike's frame or subframe at the very least.

Conversely, if you can position the bike and ground anchor such that they obscure the chain and the lock, you can make them very difficult to attack.

For example if you mount your ground anchor to a wall and positon the ends of your chain and your lock between the bike and the wall.

The Torc anchor folds so it makes it easier for you and a tougher target for the thief!

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James T

Great products

Thanks for some great products. Your kit protected my bikes perfectly during a burglary a few years ago and it’s still going (extremely) strong.

Ben R

Still going strong

I bought from you once and only needed to buy once in 2016, but suffice to say that the 19mm bespoke length chain, and ground anchor installed according to Pragmasis instructions are still going strong, keeping my bike safe just off the street in Brixton, London.

Mr B

Wholly impressed

I would like to say I am wholly impressed with the ground anchors, chains and padlocks that I have purchased over the past few years and will always recommend you when the opportunity arises.

C Rowe

Torc Ground Anchor

Excellent quality piece of kit. Our second anchor to date. Exceptional service. Nice to see a British company up there supplying quality goods and customer service

Steve

Top class service

This is a serious chain! I certainly feel more comfortable that my bikes are well secured. Very pleased with the service too. I phoned then placed an online order and my chain arrived the next day. Excellent product and 1st class service. Thank you!