OnGuard RockSolid Review: The Smallest & Lightest?

OnGuard are one of my favorite lock brands. They make competitively priced, no nonsense locks that work well, with minimum fuss.

So I was very happy to hear that they are the latest brand to produce an angle grinder resistant bike lock: the OnGuard RockSolid.

Like most OnGuard locks, it arrived with little fanfare or information, and it proved quite hard to get hold of in Europe. And while it’s not the cheapest angle grinder resistant bike lock, it’s one of the cheapest.

So how secure is it? How easy is it to carry around and use on a daily basis? And is it good value for money?

I’ve been testing it for that last couple of months to find out…

How secure is the OnGuard RockSolid?

The OnGuard RockSolid features a 15 mm steel shackle with a patented ceramic coating fused to the surface, which is designed to destroy angle grinder discs.

This rough, sparkly layer looks very similar to the one on the Kryptonite New York Diamond. And as we’ll see, in my tests, this ceramic coating performs exceptionally well (if not quite as well as the Kryptonite).

Just like all the other angle grinder-resistant bike locks, the OnGuard RockSolid is rated Sold Secure Powered Diamond, but it also has a Pedal Diamond rating too.

Against Regular Discs

With the lock taped down and using a mains-powered grinder, it only took me 1 minute in total to cut through one side of the OnGuard RockSolid shackle.

But I went through 5 discs in doing so, which is definitely at the high end compared to the other angle grinder-resistant bike locks.

And this is especially impressive considering how small and light the OnGuard RockSolid is.

However, after I had cut one side, I was able to twist open a 3 cm gap in the shackle. This is the biggest gap I have managed to prise open in all the anti-grinder locks I have tested, except for the Squire Stronghold D16 MAX, which was about the same.

Such a gap could well be large enough to remove the lock from your bike, so this is a serious fault, as in that case a thief would only need to cut the lock once to steal your bike.

And it does somewhat discredit OnGuard’s much-vaunted “X4P Quattro Bolt Locking Mechanism” that secures the shackle in four places to specifically prevent this kind of thing!

While taping the lock down and using a mains-powered grinder is a good way to eliminate variables that would make comparing the various locks more difficult, it would also be useful to know how long it would really take for a thief to defeat a particular lock in the street!

So I also test all the locks using a battery-powered angle grinder and holding the lock in one hand.

And in this test, it took me 10:46 min and 5 discs to cut both sides of the OnGuard RockSolid.

By holding the angle grinder in one hand, I’m not able to apply as much downward pressure (as when the lock is taped down and I can use two hands), so the discs don’t wear down as quickly, but they don’t cut through the lock as quickly either.

So although I am able to get through both sides with the same number of discs it took me in the first test to get through one side, it takes me much longer.

Either way, in these tests the OnGuard RockSolid is showing a high level of angle-grinder resistance.

Against Diamond Discs

It took me 5:03 min to cut through the OnGuard RockSolid with a diamond disc on a mains-powered grinder, with the lock taped down so I could use two hands.

This is a pretty impressive result and compares well with the other angle grinder-resistant bike locks I have tested.

Attack at Base of Shackle

Many angle grinder-resistant bike locks seem to have a weakness where the shackle meets the crossbar. I first encountered this when testing the Abus Super Extreme 2500, and now I attack all the locks at this point to see how they perform.

I was able to cut through the OnGuard RockSolid at this part of the shackle in 41 seconds, but it took me 4 discs to do so. This is really impressive, and it seems there is no weakness at this point on the lock.

Cutting the Crossbar

It took me 6:58 min and 5 discs to cut through the crossbar of the OnGuard RockSolid. This was using regular abrasive discs on a battery-powered angle grinder, which allows me to more easily maneuver the crossbar with one hand.

Because of the variables introduced by using one hand to hold the lock while the other wields a battery-powered grinder, it makes it difficult to compare the performance of one lock against another.

However, nearly 7 minutes of cutting with 5 discs clearly shows that the crossbar is not a weak point on this lock!

Other Types of Attack

While in theory, the 15mm shackle can be cropped by the very biggest 42” bolt cutters, it will be very difficult, and I certainly wouldn’t be able to do it.

A thief would need to get the lock in a position where they could use one arm of the bolt cutters on the floor for leverage. And if you use a good locking technique that keeps the lock away from the ground, you can make that very difficult or impossible for a thief.

A thief would also need to get a fair bit of weight on top of the other arm to generate enough force to cut a 15 mm steel shackle. Most people don’t have that sort of weight. I certainly don’t!

And of course most thieves are not going to have access to a giant pair of bolt cutters anyway!

So how secure is the OnGuard RockSolid really?

In my tests the OnGuard RockSolid performed really well against an angle grinder in every test I subjected it to.

But I have two reservations:

Firstly, that big gap after one cut could well be large enough to remove the lock from a bike after cutting just one side, which significantly reduces the amount of protection it actually provides in the street.

Secondly, although it has always performed really well in my tests, I have seen several other tests (from reviewers that I trust), where it performed much more poorly.

In the Bennets test, for example, John was able to cut one side with just one disc on a battery-powered grinder. This is just not good enough. And it suggests there are inconsistencies in the anti-grinder coating.

At the end of the day I can only really make concrete conclusions based on my own tests, and they suggest that the OnGuard RockSolid has exceptional angle grinder resistance.

Is the OnGuard RockSolid easy to carry?

The OnGuard RockSolid weighs just 1.4 kg (3.09 lb), making it the lightest angle grinder resistant bike lock, by some distance. The next lightest lock is the Litelok X1, which is 22% heavier!

This is going to make the OnGuard RockSolid easier to carry around than the other angle grinder resistant bike locks.

However, to be clear, the OnGuard RockSolid is not a lightweight lock. Its weight is equivalent to about 3.5 cans of Coke, so you should think carefully how you’re going to carry it on your bike before you commit.

Unfortunately, there is no frame mount available for the OnGuard RockSolid, so you’re limited to either buying a third party, universal solution such as the Huldit or Kryptonite Transit H Bar [Amazon], or just throwing it in a bag.

Luckily, the OnGuard RockSolid is also very small. With external dimensions measuring 9.4” x 6.7” (24 x 17 cm), it’s also the smallest angle grinder resistant bike lock currently available. So it's not going to take up much room in a bag.

I just threw it in my saddlebag. But unlike other, bigger locks, I could have also hung it over the handlebars without it getting in the way too much.

Is the OnGuard RockSolid easy to use?

The OnGuard RockSolid is definitely a mini u-lock. The internal dimensions are 3.15" x 6.89" (8 x 17.5 cm). This makes it the narrowest and the second-shortest angle grinder resistant bike lock available at the moment.

Only the Hiplok D1000 is slightly (less than a cm) shorter.

And while its diminutive size makes the OnGuard RockSolid easier to carry than other locks, it also reduces your locking options.

This is not really a bike lock for chunky ebikes, heavy city bikes or motorbikes. This is generally a bike lock for, for slim city bikes, that normally use Sheffield bike stands for locking up. And for me and my bike, that works fine!

I had no problems at all using the OnGuard RockSolid. It was plenty big enough to secure my slim city bike to all the bike stands in my city, either around the front wheel and the frame or the back wheel and the frame.

It obviously won’t fit around more chunky street furniture like a lamppost or traffic light, though.

While you might struggle to lock a chunkier bike in the traditional way, if you’re really keen on this lock, then you could invest in security skewers or Hexlox to protect your wheel, and just use the RockSolid to secure your frame.

Just be aware this is a mini u-lock, and it won’t suit all circumstances, and make plans accordingly!

Keys and Mechanism

You get 5 keys with the OnGuard RockSolid, and a key code card to order more should you need them (although how you’re going to lose 5 keys I can’t imagine!).

The keys are for a slider type mechanism, which I find far easier to use than disc detainer mechanisms (which tend to suffer from misaligned discs that can be a pain to straighten and slow down the locking and unlocking process).

The keyhole is protected from water and street grime by a sunken cover made from two pieces of metal that automatically part as you push the key into the mechanism. I really like these covers, as you don’t have to fiddle around with them before you can put the key in.

And the fact that the OnGuard covers are made from metal (other locks use plastic), adds a bit of robustness, that I also like.

I have said in the past that OnGuard locks need a little bit more TLC (cleaning and lubrication) to keep everything working smoothly. But I don’t think that’s the case anymore. I have an OnGuard Brute that stays outside in all weathers, 24 hours a day, I’ve never cleaned it and I’ve never had any problems!

So I imagine the OnGuard RockSolid is going to be just as robust over a long period of use!

Conclusion: Is the OnGuard RockSolid worth it?

OnGuard bike locks are usually really good value for money and are often very competitively priced (check Amazon price).

However, while it is usually lower priced than most of the other anti-angle grinder locks, the OnGuard RockSolid is definitely not cheap. In terms of price, its nearest rivals are usually the Litelok X1 and the SkunkLock Carbon (check Amazon price).

So how does it compare to these two locks?

While the Litelok X1 used to be significantly cheaper than the OnGuard RockSolid, it has got much more expensive in the last 12 months, and the two locks are often more or less the same price now.

In my tests the OnGuard generally had better angle grinder resistance (except in the street-style attack). But the Litelok X1 didn’t have that big gap after 1 cut. The Litelok X1 is bigger (which many people will appreciate) and has better transport options.

It’s a close call: in terms of practical security, I would say they are close enough for me to recommend that you look at which size you prefer and whether a frame mount is important to you, rather than obsess over which is the most secure.

And of course the price! Because you might be able to find the OnGuard RockSolid at a price that’s significantly lower than the Litelok X1.

On the other hand, the SkunkLock Carbon is always much cheaper than the OnGuard RockSolid. And it is a very different lock. It’s much bigger and heavier and more suited to ebikes and other bulky bicycles.

Against a standard angle grinder attack, the SkunkLock outperforms the OnGuard. But against every other attack (diamond disc, crossbar, unconventional street style) in my tests, the OnGuard was more secure.

Indeed, I feel pretty confident in saying that the OnGuard RockSolid is more secure than the SkunkLock Carbon. It’s just a case of whether you’re looking for a small lock or a bigger, cheaper lock.

In conclusion: I think the OnGuard is a great choice for those looking for a small and light angle grinder-resistant bike lock. In my tests it was very secure, but there are some doubts about how consistent that security is across different individual locks.

Alternatives to the OnGuard RockSolid

Looking for something cheaper?

So if you like the idea of the OnGuard RockSolid but can't find it at a decent price, then the Litelok X1 is a fantastic, lower priced alternative. In fact, I like it so much I made it my best bike lock top choice!

Check out my full, hands-on review of the Litelok X1 here.

Looking for something more secure?

There are a number of frame mount options available for the Hiplok D1000, which is something the OnGuard RockSolid completely lacks.

Apart from the extra weight, the only other drawback is the extra money it costs (check Amazon price here)! However, if you like the idea of a smaller u-lock and want the maximum protection, the Hiplok D1000 is a great choice.

OnGuard RockSolid Specs

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