What Thickness Security Chain Do I Need?
The right thickness comes down to one trade-off: how much you need to carry the chain versus how much attack resistance you need. As a starting point:
- 11mm — bicycles and lighter-duty use, where weight and portability matter most
- 13mm — motorcycles or bicycles where the chain needs to travel with you
- 16mm — our usual recommendation for a motorcycle kept at home
- 19mm–22mm — maximum security for stationary installations (garages, sheds, secure parking)
Portable use or home security?
For portable use, the Protector 13mm offers a practical balance of security and carrying weight. Choose the 11mm chain where lower weight is the main priority, particularly for bicycle use. The 16mm offers greater protection if you can comfortably transport it, but its weight makes it better suited to staying at your normal parking place.
For a motorcycle secured at home, we recommend 16mm as a starting point. Choose 19mm or 22mm where greater protection is needed and the chain can remain in place.
The 13mm weighs approximately 2.9kg per metre, compared with 4.5kg per metre for the 16mm. Remember to include the lock when considering what you can carry.
A noose chain may reduce the overall length and weight needed for your particular arrangement. Whichever size you choose, use a compatible lock and a strong anchor point.
At a glance
| Thickness | Best suited to | Portability |
|---|---|---|
| 11mm | Bicycles, lighter-duty security | Most portable |
| 13mm | Motorcycles/bicycles needing to travel | Portable over short distances |
| 16mm | Motorcycle or garage security at home | Usually too heavy to carry routinely |
| 19mm | High-value motorcycles, maximum stationary security | Stationary use |
| 22mm | Maximum-security stationary installations | Stationary use only |
11mm: lighter and easier to carry
Easier to handle than the larger Protector chains, but not equivalent to 13mm or 16mm in resistance. If bolt croppers are a realistic threat, move up to at least 13mm.
13mm: strong security with some portability
The practical middle ground — large enough to resist manual bolt-cropper attacks, while still manageable to carry. We recommend it for motorcycles that need to travel with the chain, or for bicycle owners who want more than a standard portable lock provides.
View the Protector 13mm Security Chain
16mm: our usual recommendation for home security
A significant step up in resistance without the extreme weight of 19mm or 22mm. Best kept at a fixed locking point rather than carried daily, and works well paired with a ground anchor. If you lock your bike in a garage or shed, the 16mm offers excellent security. However if you lock your bike outside, you might want to step up to a 19mm, depending on the threat level.
View the Protector 16mm Security Chain
19mm and 22mm: maximum stationary security
For customers who put resistance ahead of portability entirely. These chains are heavy and not a daily carry. We recommend this thickness of chain if you're securing your motorcycle for long periods of time outside.
Keep the chain off the ground
Whatever thickness you choose, a chain resting on a solid surface gives an attacker a hard surface which means they can more easily use an angle grinder or bolt croppers. A shorter, well-positioned chain will be harder to attack than a longer one left lying on the floor.
Thicker isn't automatically better
The heaviest chain only helps if it's actually used properly and consistently. A 16mm chain on a strong ground anchor, correctly positioned and locked through a solid part of the bike, will usually beat a heavier chain that's awkward to fit and gets used through a more vulnerable position, for example just through your motorcycle's front wheel.
One more check: confirm the chain's internal link clearance — not just the nominal diameter — fits your lock.
Next, read Standard chain or noose chain: which should I choose? and 13mm vs 16mm security chain.
