Bike Security Chains

Security Chains

When securing a bike on the go, you want to find the best balance between minimizing what you carry and having sufficient security for your bike.  Usually a U-Lock is the best choice as is will usually offer much more protection against bolt cutters and angle grinders and will weigh less for the same level of protection.  That said, a chain may allow you to lock your bike to objects a U-Lock won't. 

When securing your bike to a vehicle or at camp (when car camping), you don't have the same weight and bulk limitation you would if you were riding your bike.  There is no need to skimp on security if you have a vehicle.

It is also important to note that most of the places you might park, thieves in vehicles can also park their trucks and vans.  Whereas a thief on foot may just carry a single, small portable tool, a thief in a vehicle can carry an assortment of heavy duty tools.  This allows them to make small work of most security devices. 

When placing bikes on a roof rack or hitch rack, you MUST lock your bikes up.  Ideally use a high security lock and thick security chain.

Avoid use of Security Cables!  These are easy to cut with a hacksaw or bolt cutters!

Recommendations

• Mobile Security

  • Ideally use a U-Lock

    • A U-Lock generally provides better security than a chain and is often lighter for comparable security

  • If you use a chain, use 8 or 10mm security chain

    • Use a 10mm security chain for the frame and rear wheel

    • You can use an 8 for a secondary lock, such as to secure your front wheel

      • an 8mm chain provides Silver level protection

    • Example Brands

      • Kryptonite or Abus

      • Hiplok makes chains you can wear around your waist

      • If you have lots of money - Pewag or Squire

    • Must use High Security Lock with Chain

• Static Security

  • 10mm+ (ideally 12) security chain for pedal bikes

  • 12mm+ security chain for powered bikes

  • Example Brands

    • Quality: Kryptonite and Abus

    • Premium: Pewag and Squire

  • Must use a High Security Lock with Chain

• Vehicle Security

  • Bikes placed on a bike rack on a vehicle need to be locked up

  • Your level of security is often limited to what you secure the bike to

    • Roof Racks

      • Often made from thin metal or aluminum - easy to cut through with saw

      • A 10mm security chain is likely more than sufficient for roof mounts

    • Vehicle Frame

      • A 12mm security chain is very difficulty to disable

      • Only beneficial if you are securing the chain to part of vehicle that is more difficulty to cut through or access

        • Secure around Frame (trucks) or around hitch if possible 

        • Secure with High Security Lock in location where it is difficult to access

Chains

• Bolt Cutters

  • The larger, the chain link, the more difficult they are to cut with bolt cutters

  • <13mm Chain links can be cut with medium bolt cutters

  • 12-15mm Chain links can be cut with long bolt cutters (36-42") using leverage

  • 16mm Chain links can not be cut with bolt cutters

  • If you keep the chain off of the ground, it will be much more difficult to defeat them with bolt cutters

• Angle Grinder

  • ALL chains can be cut with an angle grinder

  • Larger chains take longer to cut

    • 22sec for 8mm (5/16") (cutting through both sides in ideal conditions)

    • 26sec for 10mm (3/8")

    • 40sec for 12mm (1/2")

  • Square links last a little longer than round links

  • See.youtube AM9mPHoWiSY 

• Alloy and Hardening

  • Alloy and hardened steel is much more resistant to bolt cutter and saw attacks than regular carbon steel 

  • Alloy Steel

    • Quality security chains are made from alloy steel

    • Alloy provides a balance of strength, toughness, and resistance to corrosion compared to regular carbon steel. 

  • Case Hardening

    • Chain links are heated and infused with carbon to create a hard outer layer 

    • In this method, the core remains slightly softer, keeping the link overall flexible 

    • The hardened surface makes it difficult for bolt cutters and saws to penetrate the chain links 

    • Hardening also improves wear resistance, which is important for other applications other than security 

  • Hardness matter with Bolt Cutters

    • To resist bolt cutters, you want a chain that is harder than the bolt cutters attacking them

    • 41 Rockwell Hardness - Grade 120 Chain

    • 59-60 Rockwell Hardness - Conventional Bolt Cutters 

    • 62 Rockwell Hardness - Pewag Security Chain

    • 65 Rockwell Hardness - Squire Security Chains 

    • 65 Rockwell Hardness - Abus Granit Padlocks

• Square vs Round Links

  • Square links increase contact area for bolt cutters, making them more resistant to bolt cutter attacks

  • Square links are more resistant to saw attacks

  • Educated thieves may be more will to attempt to cut a chain with round links and pass on on with square links since they are more likely to be made from hardened steel

• Chain Brand

  • It is difficult to compare chain performance between different brands since few companies publish their specs

  • Here are the perceived ranking of security for different brands of the same sized chain from least secure to most secure

    • Regular Steel Chain

    • Grade 70-120 Chains

    • Chinese Security Chains

    • OnGuard

    • Kryptonite

    • Abus

    • Pewag (Rockwell 62)

    • Squire (835VPN)

• Chain Size

  • Size Matters

    • Larger chains are more saw, cutter and grinder resistant

    • Larger chains are also more expensive and heavy

  • 7mm

    • Minimum size for Bike Chain

    • ~1/4"

    • Relatively easy to cut with bolt cutters

    • Examples:

      • Seatylock Viking Silver - Silver

      • PEWAG Security Chain

        • 10% case hardened

        • Rockwell Hardness of 62

        • Also sell chafe sleeves (separately or in kit)

  • 8mm

    • Silver Rating

    • ~5/16"

    • Can be cut with medium bolt cutters

    • Common size chain in US Hardware Stores

      • Get at Harbor Freight, Tractor Supply, or Northern Tool

      • Regular grade chain is MUCH softer than security chain and are easier to cut with bolt cutters

        • Look for Grade 70, 80, 100 or better

      • Cutting with Bolt Cutters requires right tool and about 180 pounds with concrete backing and ~30 seconds of fussing

      • Requires at least 2.1" tube to cover chain 

    • Examples:

      • Hiplok Original

        • Silver Rated 2 stars

      • Abus 8K 

        • Has oversized link on one end, which allows you to run the link on the other end through it

          • Allows you to use locks with a narrower shackle 

      • Squire Hardened Alloy Steel Chain | J4

        • Sold Secure Silver Bicycle approval 

  • 9mm

    • Lower end of Gold Rating

    • Examples:

      • Kryptonite KryptoLok - Gold 2 Stars

      • Abus CityChain - Gold

  • 10mm

    • ~3/8"

    • Preferred size for locking up a bike

    • Gold Rating

    • Difficult to cut with medium sized bolt cutters

      • Requires some skill and leverage

      • Longer bolt cutters will easily cut these

    • Common size chain in US Hardware Stores

      • Get at Harbor Freight, Tractor Supply, or Northern Tool

      • Regular grade chain is MUCH softer than security chain and are easier to cut with bolt cutters

        • Look for Grade 70, 80, 100 or better

      • Requires at least 2.3" tube to cover chain 

    • Shorter chains are a bit heavy to travel with

      • Anything larger or longer is really too heavy to carry when biking

    • Examples:

      • Kryptonite Evolution - Gold 3 Stars

      • Abus Granit CityChain - Gold 3 Stars

      • Hiplok Gold - Gold 2 Stars

      • Hiplock Homie - Gold 2 Stars

      • OnGuard 8019L Mastif

      • Abus 10K 

        • Has oversized link on one end, which allows you to run the link on the other end through it

          • Allows you to use locks with a narrower shackle 

      • PEWAG Security Chain

        • 10% case hardened

        • Rockwell Hardness of 62

          • Considered harder than other security chains

          • Claims 42" Bolt Cutter "Proof"

        • Also sell chafe sleeves (separately or in kit)

        • Pewag VKK10x35 Chain is Gold Rated

      • Squire Stronghold Hardened Alloy Steel Chain 

        • 835VPN Hardness (close to Rockwell C 65 HRC)

        • Hardened Alloy Steel Chain 

          • G3 36-inch (915mm) chain length

          • G4 47.2-inch (1200mm) chain length

          • IC/850 Squire Stronghold Hardened Alloy Steel Integrated Chain Lock

          • Chain is Sold Secure Gold Bicycle (integrated lock is Diamond)

  • 12mm

    • ~1/2"

    • Short chains can be used for mobile security, but generally for stationary security

    • Very Difficult to cut with medium sized bolt cutters

      • Requires some skill and leverage

      • Longer bolt cutters will easily cut these

    • Very Heavy

    • Kryptonite and Abus have a Ring at the end of their chains allow for "noose" use

      • Reduces overall length needed to secure bike to anchor

    • Examples:

      • Kryptonite New York Noose

      • Abus 12KS Loop 

        • Has large loop on one side to allow for "noose" use

      • PEWAG Security Chain

        • 6% case hardened

        • Rockwell Hardness of 62

          • Considered harder than other security chains

          • Claims 42" Bolt Cutter "Proof"

        • Also sell chafe sleeves (separately or in kit)

  • 14mm

    • ~9/16"

    • Made for High Security overnight at home

    • Far Too Heavy to carry on bike

    • Almost bolt cutter proof

      • 13-15mm links require 36 or 42" bolt cutters

    • Diamond and Motorcycle Gold

    • Examples:

      • Kryptonite New York Fahgettaboudit

      • Hiplok XL Noose

      • OnGuard 8016 Beast

      • Squire TC 14/3 and TC 14/4

  • 15mm

    • ~19/32"

    • Examples:

      • Kryptonite New York Legend

        • ART5/5 stars

  • 16mm

    • ~21/32"

    • Can not be cut with bolt cutters

    • Pedal Diamond

    • Example:

      • Squire Hardened Alloy Steel Chain | TC16/5

Locks

• ABUS Diskus 20/80 Heavy Duty Stainless Steel Disk Padlock 

  • Rustrpoof

  • 7/16" Shackle

• ABUS Granit 37/80 Heavy Duty Hardened Steel Padlock -

  • 1/2" Shackle

  • Expensive