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Squire Defiant review | Angle grinder-resistant motorcycle disc lock tested

Consumer Editor of Bennetts BikeSocial



Squire Defiant disc lock review_03
Squire Defiant disc lock review_04


Date reviewed: June 2023 | Tested by: John Milbank | RRP: £199.99 | Weight: 1.05kg |


The Squire Defiant on review here is one of the toughest disc locks you can buy, and promises to be resistant to all forms of attack thanks to an angle grinder-resistant construction, one-piece all-metal body and six-pin dimple key cylinder.

Two keys are supplied, along with a code card if you need any more cut. A neoprene pouch is also included, along with a coiled reminder cable.

We put the Defiant through our full destruction testing to find out if it’s worth the money…


  • Extremely resistant to all forms of real-world attack

  • Easy to fit and remove

  • Padded case & reminder cable included

  • Brake disc is the vulnerable point of attack

  • Not suitable for scooter discs


Size and weight

The Squire Defiant motorcycle disc lock has a plastic cover and is 30mm thick (the metal body itself is a shade under 25mm thick), 85mm wide and 77mm tall, with an additional 17mm of the 12mm diameter shackle poking out, which is made of hardened boron steel.

The Squire Defiant weighs 1.05kg.



Day to day use

While the well-made pouch that’s supplied includes a belt-loop and hook, I’d not recommend wearing it as it could cause injury in a crash. However, as something you could attach to a luggage strap on the bike, or tuck into a top-box, pannier or tank-bag, the Squire Defiant is compact and easy to stash, with the carry pouch protecting anything else it gets thrown in with.

The coiled reminder cord fits into the pouch with the lock, and can be looped around the Squire, and the end of your bike’s handlebar (or front brake lever if you have handguards fitted).

The lock’s very easy to attach, and had no problems fitting around the rims then locking onto the discs of a BMW R1250GS, a 1999 Kawasaki ZX-6R and a 2001 Honda VFR800. The key is not directional, being the same cut on both sides, which makes it easier to use.

Removing the key can feel a little awkward at times, but release any anti-clockwise pressure when turning and it slips out fine.



Resistance to attack

Being such a large lump of metal, and thanks to its 12mm diameter shackle pin (which locks on both sides of the opening), attacking the Squire Defiant with a lump hammer does nothing more than damage the plastic cover and put some dents into the body. The outer part of the locking pin did fall off during the hammer attack, but this doesn’t affect the security at all. I was also able to push it back in and operate the key to open the shackle after sustained attacking.

Motorcycle thefts do not always involve an angle-grinder, and thieves have even smashed off a lightweight disc lock with a lump of stone, so having a chunky locking pin (which won’t always fit a scooter), and a solid body provides a valuable line of defence.

Pry bars and other forms of splitting attack aren’t effective on the Squire Defiant.

If a thief is equipped with an angle grinder, the Defiant itself is extremely robust thanks to the thick metal construction throughout and additional angle grinder-resistant material in the most vulnerable area that forms the bridge between both sides of the disc.

Gaining access to the bridge of the Squire with an angle-grinder can be awkward depending on the size of the bike’s wheel rim, but even under ideal conditions it took at least two abrasive discs in my testing to cut through it. Using a diamond cutting disc was still very time-consuming.

After all the attack testing, and despite the lock being in two parts, I was still able to operate the lock barrel with the key.

To see how this compares with the other locks we’ve tested, check out our best motorcycle locks for home and away.



Sold Secure rating

The Squire Defiant, which is made in Britain, has been tested to Sold Secure’s highest ‘Powered Cycle Diamond’ standard (this used to be called Motorcycle Diamond), which requires the lock to stand up to the testing body’s angle grinder for at least 90 seconds, as well as withstand other attacks including lock picking.

While videos of lock picking prove extremely popular for the influencers looking to sell their own tools, according to the police and the International Association of Auto Theft Investigators, it’s still not an attack that’s occurring in the real world of motorcycle theft. Despite this, Sold Secure – which is part of the Master Locksmiths Association – does run picking tests to ensure locks it rates are properly constructed.



Bennetts BikeSocial test results

Product: Squire Defiant disc lock

Weight as tested: 1.05kg

Pry bar attack: GOOD

Lump hammer attack: GOOD

Angle grinder attack: EXCEPTIONAL


Squire Defiant review: Verdict

While expensive, the Squire Defiant is an extremely tough disc lock, which stands up well to all common forms of attack, though if a thief does use an angle grinder, the brake disc itself remains the most vulnerable link in the setup. While many won’t mind causing damage here, there will be circumstances where they don’t want to, for instance if the bike’s going to be ridden in another crime. And angle-grinders are not used in all thefts – some will even use large stones to smash a lock off if it’s weak enough.

Using even a lightweight disc lock can reduce the chances of theft by a factor of three, and the more obstacles you can put in a criminal’s way, the less likely they are to attempt to steal your bike… or be successful if they do try. On its own, or as part of multiple security items, the Squire Defiant is a solid piece of kit.

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