Bike Locks Tested: Which Models Resist Cutters and Angle Grinders

Introduction

A bike lock only has to fail once, and the cost of that failure is the whole bike. That makes cut resistance the single most useful thing to understand before buying, and it is also the hardest thing to judge from a product page.

This guide covers eight locks that carry recognised Sold Secure ratings, from lightweight wearable designs through to heavy models marketed specifically as angle-grinder resistant. Each one was attacked with cutting tools under a strict 10-minute limit per attempt, and the recorded times split the group into three clear tiers.

How These Locks Were Tested

Every lock was given one 10-minute window. Cutting was aimed at the lock body, bar or chain, and the clock stopped as soon as the lock could be released and the bike freed. Two of the eight ran past the full 10 minutes and were stopped by the time limit rather than by the lock giving way.

One lock in this group was bought at retail, while the others were supplied by their manufacturers for testing. Prices quoted below are the figures given at the time of testing, and several models are widely available for less than their headline RRP.

Squire Straplock 35

The Squire Straplock 35 is a wearable lock with a quoted RRP of $69.99 and a Sold Secure Silver rating. It is built from multiple high-tensile steel cores and is designed to sit comfortably on the body while staying friendly to a bike frame. In testing it was the quickest of the group to open, giving way in 55 seconds, which places it firmly in the lightest-duty tier here.

Kryptonite Evolution Mini

The Kryptonite Evolution Mini is a Sold Secure Gold lock selling for around $85, and it ships with a cable for securing a second wheel or accessory. Its useful detail is that both arm ends lock into the body, so cutting through one side is not enough on its own: the second side still has to be cut before the lock can be removed. That extra step helped it reach 4 minutes and 4 seconds.

Squire Chain Lock 10

The Squire Chain Lock 10 is a wearable chain lock with a quoted price of around £90 and a Sold Secure Diamond rating, the highest rating in this group. The chain is made from 10 mm hardened square alloy steel, and it was the best-rated lock in the test set at that point.

At 4 minutes and 12 seconds it lasted a fraction longer than the Kryptonite Evolution Mini, and the gap between the two is small enough that they belong in the same tier. Riders who want something wearable, highly rated and clearly tougher than a strap lock will find this the more convincing option of the two.

Squire Stronghold FL 850

The Squire Stronghold FL 850 is a folding lock with a Sold Secure Gold rating and the first folding design in this test group. Its plastic outer sleeve, which exists to protect the bike frame from scratches, came away almost immediately once cutting began. It opened in 54 seconds, the shortest time recorded, and it is also heavy and bulky to carry around.

OnGuard Pitbull

The OnGuard Pitbull carries a $39.99 RRP and is marketed towards moped riders, although it works just as well on a bicycle. It holds a Sold Secure Diamond rating, and it can often be found online for considerably less, around £25, which makes the rating look like unusually good value. In testing it lasted 3 minutes and 2 seconds, putting it in the middle tier rather than at the bottom.

Squire Stronghold D16 Max

The Squire Stronghold D16 Max is sold as an anti-angle-grinder lock at £130, with a Sold Secure Diamond rating. It has a rubbery coating around the outer body that was cut through quickly, but the metal bar underneath was barely marked. The lock ran past the full 10-minute limit, and the attempt was abandoned with the lock still doing its job.

The other thing worth knowing is how loud it is when attacked, which is a genuine practical advantage in a public place. The trade-off is weight and bulk: at £130 it costs less than half the price of the most expensive lock here, but it is the kind of lock most riders would leave at a regular parking spot rather than carry every day.

Hiplok DX1000

The Hiplok DX1000 is a £300 anti-angle-grinder lock with a Sold Secure Diamond rating, a lifetime warranty and a design aimed mainly at motorcycles and e-bikes. It also comes with a mounting arm that can be fixed to a garage floor so the lock can be left in place, and the full setup including that arm is quoted at £600.

It performed best of everything tested. After a full 10 minutes of cutting, the attacker had worked partway into one side while the opposite side remained largely intact. Because both sides have to be cut, the realistic time to defeat it is closer to 20 minutes, and the lock body visibly changed colour under the blade without opening. A thinner model in the same family was previously cut through one side in about five minutes.

Squire IC 850

The Squire IC 850 is a large chain lock with a Sold Secure Diamond rating. It held out for 6 minutes and 25 seconds, which places it clearly ahead of the mid-tier locks but short of the two anti-angle-grinder models. For riders who prefer a chain to a rigid lock, it is the longest-lasting option in this group.

Buying Advice: Matching a Lock to How You Ride

The results fall into three broad bands. Wearable and chain locks that are easy to carry tended to open in about a minute, heavy-duty locks lasted roughly three to five minutes, and the two anti-angle-grinder models ran past the 10-minute limit entirely.

For most riders the four-to-five-minute mark is a sensible balance between cost and resistance, and the Kryptonite Evolution Mini, the Squire Chain Lock 10 and the OnGuard Pitbull all sit in or near that band at very different prices. If the bike is parked in the same place every day, a heavier anti-angle-grinder lock left at that spot makes more sense than carrying one around: the Squire Stronghold D16 Max delivers that level of resistance at £130, while the Hiplok DX1000 is the strongest lock tested but costs more than twice as much and is heavier again. It is also worth remembering that a determined thief may simply cut whatever the bike is locked to, so the anchor point deserves as much attention as the lock itself.

Conclusion

No lock here is unbreakable, but the spread in cut times is wide enough to matter. If you carry your lock with you, the Squire Chain Lock 10 and the Kryptonite Evolution Mini are the sensible picks in the wearable and mid-weight bracket. If the bike stays in one place, the Squire Stronghold D16 Max gives the longest resistance for the lowest price among the anti-angle-grinder models, and the Hiplok DX1000 is the strongest overall.