I tried one of the toughest bike locks on the market — and now my U-lock looks downright puny

Abus Granit Super Extreme 2500 bike lock on a red table.
(Image credit: Dan Bracaglia/Tom's Guide)

Abus is a German company with roots in lock manufacturing that go back to the early 1920s. These days, the brand makes a wide range of bike accessories, including some of the best bike locks money can buy and my favorite bike helmet, the Abus Gamechanger 2.0

The latest product, the Abus Granit Super Extreme 2500, is a burly, tough-built U-lock packed with technology to protect your precious ride from potential theft. And while no bike lock on Earth is completely impenetrable, this Abus U-lock is designed to survive run-ins with electric angle grinders, a sworn enemy of bike locks everywhere. 

I used the Abus Granit Super Extreme 2500 to secure an ebike while running errands around town. Over the course of several short trips, I got a sense of how easy this lock is to use and carry. I also compared it to my tried and true Kryptonite Kryptolok Series 2, which has served me well for 15-plus years. 

Here are my initial impressions of the Abus Granit Super Extreme 2500 after a few weeks of use. 

1. It's a lot tougher than my current bike lock

Abus Granit Super Extreme 2500 bike lock on a red table.

(Image credit: Dan Bracaglia/Tom's Guide)

It's not even close, the Abus Granit Super Extreme 2500 is way beefier than my current bike lock, though the Abus lock also costs roughly five times as much. Still, my Kryptonite Kryptolok Series 2 has ably protected a small arsenal of beloved single-speed and geared bikes over the years I've been using it.

However, now that I've laid paws on the Super Extreme 2500, my old go-to is looking extra wimpy. The two locks are roughly the same size and shape, with an inner shackle space of around 4 x 9 inches, but the Abus shackle and crossbar are easily double the thickness of the Kryptolok.

The Super Extreme 2500 also has dual locking cylinders in the crossbar body, while my Kryptonite only has a single one, presumably making it easier to pick. Finally, the Abus weighs twice as much as my Kryptolok: 5.2 pounds compared to 2.6 pounds. 

2. Tungsten carbide repels angle grinders

Abus Granit Super Extreme 2500 bike lock on a red table.

(Image credit: Dan Bracaglia/Tom's Guide)

Before the Super Extreme 2500, my only worldly interaction with the word "wolfram" was courtesy of an episode of Seinfeld where George makes a lifestyle change, resulting in super-intelligence; but, I digress.  

Wolfram (or tungsten) is a rare earth metal that becomes extra tough when formed in a compound with carbon, i.e. wolfram carbide. Why the chemistry lesson? The entire outer of the U-lock, including the shackle and crossbar/body, is coasted in a wolfram carbide for top-notch protection against battery-powered angle grinders. 

This outer coating essentially dulls out the grinder blade before it can come close to cutting through the shackle or crossbar. Take that, bike thief jerks! 

3. It's easy to use but the schakle could be longer

Abus Granit Super Extreme 2500 bike lock on a red table.

(Image credit: Dan Bracaglia/Tom's Guide)

The lock mechanism on the Super Extreme 2500 is extremely smooth and easy to operate. The keys slide in either direction, and a 180-degree turn unlocks the shackle.  A gentle pull removes the crossbar. 

As mentioned, you get around 9 inches of clearance inside the U, which was easily enough to lock up the frame of a Trek Verve+ 1 Lowstep LT to just about anything.

However, I was unable to get the lock through both my front wheel, the frame and a bike rack or a balcony railing. This method of locking up has been my standard practice for two decades in two different cities, New York and Seattle. So, leaving the Trek secured through only its frame left me quite uneasy during my testing. Fortunately, the bike was left untouched. 

That said, I'd love to see Abus offer a second, longer version of the Super Extreme 2500 with an additional 3 or 4 inches of clearance. 

4. Lost keys? No problem

Abus Granit Super Extreme 2500 bike lock on a red table.

(Image credit: Dan Bracaglia/Tom's Guide)

The Abus Granit Super Extreme 2500 comes with two sets of keys, which is pretty standard for U-locks. However, you also get a personal code that can be used in the event you misplace both sets. Or, if you lose one, you can request a replacement from Abus with ease. 

As you might expect from such a high-end lock, the Super Extreme 2500 boasts the brand's most pick-proof cylinder technology. The structure and housing of the cylinder and shackle locking mechanisms are additionally made of hardened steel for added theft resistance. 

5. It's probably a better choice for ebikes

Abus Granit Super Extreme 2500 bike lock on a red table.

(Image credit: Dan Bracaglia/Tom's Guide)

Weighing just over 5 pounds, the Super Extreme 2500 is a lot of lock to lug around, particularly if you're riding a standard mechanical bike. But for ebike owners, it makes a lot of sense. The best electric bikes are often pricier than their old-school counterparts, so maximum protection is paramount. It's also a lot easier to schlep a heavy lock around town when you've got an onboard motor. 

The Super Extreme 2500 starts at $329 for the lock only. For $396 you can pick up the lock and a bike frame mounting bracket. Sure, $400 sounds like a lot of coin for a bike accessory but if it protects your $2,000 ebike from theft just once, the cost becomes much easier to justify. 

Ultimately, I don't own an ebike, but if I did, I'd be strongly considering this U-lock along with the Hiplock D1000, which offers similar angle-grinder resistance tech and overall beefiness for about the same price. 

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Dan Bracaglia
Senior Writer, Fitness & Wearables

Dan Bracaglia is the Tom’s Guide editorial lead for all things smartwatches, fitness trackers and outdoor gear. With 15 years of experience as a consumer technology journalist testing everything from Apple Watches to instant cameras, Dan is deeply passionate about helping readers save money and make informed purchasing decisions. In 2024 so far, Dan’s tested dozens of wearables, including the latest devices from Apple, Google, Garmin, Fitbit and Samsung.

An avid outdoor adventurer, Dan is based in the U.S. Pacific Northwest where he takes advantage of the beautiful surroundings every chance he gets. A lover of kayaking, hiking, swimming, biking, snowboarding and more, he also makes every effort to combine his day job with his passions. When not assessing the GPS and heart rate accuracy of the latest Fitbit, you can find him photographing Seattle’s vibrant underground music community.