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OnGuard Bulldog DT Review

The Bulldog is large and accommodating, but if you're in need of a U-lock for higher security needs, this one might not be the best option
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Price:  $45 List | $41.24 at Amazon
Pros:  Inexpensive U-lock, durable, good quality
Cons:  Lacks the security of better U-locks, clunky design, mount is not our favorite
Manufacturer:   OnGuard
By Rebecca Eckland ⋅ Review Editor  ⋅  Apr 20, 2020
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50
OVERALL
SCORE


RANKED
#15 of 17
  • Security - 40% 5
  • Ease of Transport - 25% 4
  • Ease of Use - 20% 6
  • Versatility - 15% 5

Our Verdict

The OnGuard Bulldog DT is a decent U-lock for a lower price than most that come from reputable lock companies. The U-Lock is a bit larger than most, which makes it more likely to accommodate the front (removed from the front fork) and back wheels of your bike, the bike frame, and the bike rack. It also comes with a mount so that you can attach the lock to your bike frame, but we didn't like it very much. The robust mount and the lock's design make it a solid medium-security U-lock. It has a double-locked shackle design that, according to the manufacturer, requires that bike thieves make two cuts on the U-lock and not just one, which adds to its security. We were able to defeat it with one cut through the shackle with an angle grinder.

Compare to Similar Products

Our Analysis and Test Results

Performance Comparison


The Bulldog U-lock and cable combo is a basic  but decent  bike lock.
The Bulldog U-lock and cable combo is a basic, but decent, bike lock.

Security


We didn't find much to get excited about in terms of security. Granted, it's a less expensive U-lock, but OnGuard gives the Bulldog DT a "70" or "high security" rating according to its own internal rating system. If they are referring only to the U part of the lock, we would tend to agree. However, our testers discovered that the shackle is this lock's vulnerable spot.

The 13mm thick U of hardened steel was easier and faster to cut through with the angle grinder than higher-end U-locks.
The 13mm thick U of hardened steel was easier and faster to cut through with the angle grinder than higher-end U-locks.

For thieves with hand tools, the Bulldog is burly: there's no getting through this lock with hammers, tin snips wire cutters or bolt cutters. Once you introduce power tools into the equation, it's over, as with all locks. What downgrades the score of this lock is how quickly we were able to cut through this lock in comparison to other, thicker U-locks we tested. The lock easily succumbed to an electric-powered angle grinder within mere seconds. The worse news? If thieves can cut through the shackle (which we accomplished much easier than we expected), that disables the metal plate that locks the U into the shackle-- so in one cut, it's possible to nab your bike. We generally recommend U-locks that require two cuts to the U portion, or at least a shackle that's more difficult to cut through.

The shackle was the weak point for this lock...and once the shackle is compromised  your bike is as good as gone.
The shackle was the weak point for this lock...and once the shackle is compromised, your bike is as good as gone.

Ease of Transport


If you're not exactly "handy", installing a bike mount could be something of an adventure. Perhaps having this in mind, the designers at OnGuard created a bike mount that is simultaneously robust and easy to install, even if you're not all that skilled at that sort of thing. The low-profile mount fits on most frames and keeps the lock in place even on some considerably rough roads. The mount is sturdy. However, many of our testers didn't love that it positions the 3-pound lock off-center on the bike. We prefer lock mounts that keep the lock streamlined with the bike frame. If you're toting the included cable around for additional security, it will need to be carried in a pack.

The mount that comes with the OnGuard BullDog is reliable on paved roads  but if your ride is particularly rough  you might want to look for other frame mounting options. We also wish it didn't stick off-center from our frame.
The mount that comes with the OnGuard BullDog is reliable on paved roads, but if your ride is particularly rough, you might want to look for other frame mounting options. We also wish it didn't stick off-center from our frame.

While the OnGuard Bulldog isn't the heaviest U-Lock in our lineup, we bet you'll notice the extra three pounds of weight on climbs no matter if the lock is mounted to your frame or is stuffed into your backpack. That's just part of being a U-lock, and actually, this one is lighter than several models. It's also a larger lock, so if you ride a smaller frame (read: 50cm or smaller) you might not be able to mount this lock directly to your frame. Larger sizes mean they can fit around more objects but also more of a bear to transport.

The On-Guard BullDog DT lock offers medium security and a surprising bit of versatility for a low-cost U-lock. Here  the lock is shown with an after-market mount that holds the lock more securely.
The On-Guard BullDog DT lock offers medium security and a surprising bit of versatility for a low-cost U-lock. Here, the lock is shown with an after-market mount that holds the lock more securely.

Ease of Use


Even though the locking mechanism is often noted for its security, our testers complimented the OnGuard Bulldog for how easy it was to use. There was no fighting or odd "grippiness" to this lock: every time we used it, it came apart and locked up smoothly.

With five keys  a nice size-U and an easy-to-use lock  there was a lot to like about the OnGuard Bulldog.
With five keys, a nice size-U and an easy-to-use lock, there was a lot to like about the OnGuard Bulldog.

We also appreciated the fact that this lock comes with five keys — one of which has a light on it. If you're a busy bike commuter, it stands to reason that you might misplace a key. Having four extras is wonderful insurance that you won't run out of them too quickly.

What is not easy to use is OnGuard's protection policy which claims that it will reimburse you up to $1501 if your bike is stolen using their lock. What they put in the fine print is that you have to register your lock and pay to register it in order to qualify. And if you happen to have your bike stolen and you want to collect on this policy, you must provide them with receipts for the lock, the bike, an evaluation of the value of the bike and then proof that the lock failed (most often: the broken lock itself.) As you can imagine, this isn't an easy thing to do. Because of this, we didn't add any extra points to this metric because we assume most riders will not be able to collect on this policy. Most theft insurance policies follow this scheme (OnGuard is not the only company to flash big dollar signs and then have tough stipulations). For this reason, we don't put much weight behind these theft protection policies.

The On-Guard BullDog DT lock offers ample versatility for a low-cost U-lock.  We were able to lock both our wheels to most bike racks with the Bulldog. The cable is useful to secure our bike saddle  when necessary.
The On-Guard BullDog DT lock offers ample versatility for a low-cost U-lock. We were able to lock both our wheels to most bike racks with the Bulldog. The cable is useful to secure our bike saddle, when necessary.

Versatility


Our testers were impressed with this U-Lock that enabled us to lock our commute bikes to pretty much any bike rack-- and to do so using the most secure method (locking the front and back tire next to the frame and to the bike rack). There were only a handful of situations where we encountered a bike rack or on the trailhead where, due to the constraints of simply being a U-Lock, we couldn't lock our bike securely. In conventional urban settings, this lock is adeptly versatile.

The Bulldog DT lock offers average security and a surprising bit of versatility for a low-cost U-lock.
The Bulldog DT lock offers average security and a surprising bit of versatility for a low-cost U-lock.

The 4-foot cable that is included with the U-Lock could make this lock a bit more versatile if you live and commute in a low-risk area. However, we always recommend locking both tires to the frame and bike rack. If you're looking for a lock in even a medium-risk area, the included cable isn't going to do much than to deter a snatch-and-grab opportunist. Note: The cable cannot be used on its own, and once the U-lock is defeated, the cable is also defeated.

The longer-than-most U bar adds to the versatility of this U-lock  allowing it to accommodate more objects inside the lock.
The longer-than-most U bar adds to the versatility of this U-lock, allowing it to accommodate more objects inside the lock.

Value


When you're in the market for a bike lock, less isn't always more…especially when it comes to the price. Granted, we love a good bargain just like the next person, but if you need a U-lock to meet your security needs, we think there are better options out there. At its exact price point, it's actually the best U-lock we know. However, we would recommend that our biking friends spend only a bit more money to get a better lock.

While the OnGuard BullDog comes with a 4' cable  we wouldn't recommend using it to secure expensive components unless you are in a low-risk area.
While the OnGuard BullDog comes with a 4' cable, we wouldn't recommend using it to secure expensive components unless you are in a low-risk area.

Conclusion


If you've decided there's enough risk where you're riding to merit a U-lock, there are plenty of other options out there that don't cost a whole lot more, but that will offer you more security and peace of mind. The OnGuard Bulldog DT is ok, but its clunky design, off-center mount, and lower security (as far as U-locks are concerned) didn't fully impress us.

Rebecca Eckland