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…
The smallest and lightest angle grinder resistant bike lock with very impressive resistance in my tests, but a lower Sold Secure rating.
Summary
OnGuard RockSolid Pros
OnGuard RockSolid Cons
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 repel angle grinder discs. In this way it is much like the Litelok X series.

The textured part of the shackle is the ceramic coating
And as we’ll see, in my tests, this ceramic coating performs exceptionally well.
However, I should note that Sold Secure have “only” awarded it a Pedal Diamond rating, rather than the higher level Powered Diamond rating that all the other angle grinder resistant locks have been awarded.
I suspect that this is because OnGuard didn’t submit it for testing in this category, and not that Sold Secure discovered a weakness related to the relatively thin shackle or the locking cylinder.
And OnGuard probably didn’t submit it because the RockSolid is so small, it’s clearly not really suitable for motorbikes, and they didn’t realize (or don’t care) that the testing criteria is higher for the Powered Cycle rating.
Anyway, I certainly wouldn’t let it put you off buying this lock, because against an angle grinder it performs really well…
Against Regular Discs
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 one of the highest number in all of my tests of angle grinder resistant bike locks!
This is especially impressive considering how small and light the OnGuard RockSolid is.
I didn’t cut the other side as I didn’t have enough discs! But if we extrapolate the numbers, it seems like it might take 2 minutes and 11 discs to cut both sides. And of course if you factor in the time it takes to change the discs, it would be far, far longer than 2 minutes!

I was able to open quite a big gap after 1 cut
However, after I had cut one side, I was able to twist open quite a gap in the shackle. Whether this would be large enough to remove the lock from your bike (especially if you have locked it well, by filling the shackle), is debatable.
And it’s certainly a smaller gap than I was able to open after cutting the Squire Stronghold D16 MAX.
But it is slightly concerning, and 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!
Against Diamond Discs
I haven’t properly tested the OnGuard RockSolid against a diamond disc yet. When I did try with a diamond disc that had already been used on another lock, the disc kept sliding across the surface of the metal and I was unable to make any kind of cut.

The diamond disc I used just slid across the surface. Was it blunt?
I’m presuming this is because, the disc was blunted by the other lock, though.
I will be testing again in a week or so, and will update this section when I have tried a new diamond disc against the RockSolid.
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.

It was very difficult to cut the OnGuard RockSolid at the base of the shackle
I was able to cut though 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.
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.

The 15 mm shackle is one of the thinnest of all the angle grinder resistant bike locks
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!
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!

OnGuard RockSolid: the lightest angle grinder resistant bike lock
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.

It weighs about the same as 3.5 cans of Coke
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.

It takes up very little room in my saddlebag!
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.

It's the narrowest and second-shortest angle grinder resistant bike lock
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!

Plenty big enough for my slim bike on a Sheffield bike stand
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 fits around the front wheel as well!
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.

This way works too!
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!).

You get 5 keys and a key code card
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.

OnGuard RockSolid's metal keyhole cover
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, meaning you can often find them for very competitive prices!
However, the OnGuard RockSolid is definitely not cheap. The price on the OnGuard website and on Amazon, makes it mid-range. Both the Litelok X1 and the SkunkLock Carbon [Amazon] are cheaper.
But to be fair, everything else is more expensive.

OnGuard RockSolid unboxed
Based on my tests, this seems completely reasonable. It’s much more angle grinder resistant than the Litelok X1. And while it didn’t perform as well as the SkunkLock Carbon in my latest test, I have some reservations about the overall security of that lock that you can read here.
It doesn’t come with a frame mount, but it’s small and light enough for that not to be a big deal for most people (it will sit comfortably in a bag or hung over the handlebars). It will also fit a number of third party mounts and straps.

OnGuard RockSolid boxed
I wouldn't let the lower Sold Secure Pedal Diamond rating put you off buying this lock. I think it is simply because it wasn't submitted for testing in the Powered Diamond category, because it's too small for many powered bikes (motorbikes).
Because in my tests, against angle grinders, it performed fantastically well!

Unlike the Hiplok D1000 & Litelok X1 the OnGuard RockSolid only has a Pedal Diamond rating
One last point: I have seen this on sale at various different prices in various different places. So shop around. If you can get it at a price approaching the Litelok X1, then snap it up, as that would be fantastic value for money!
Alternatives to the OnGuard RockSolid
Looking for something cheaper?
The Litelok X1 is one of the lowest priced angle grinder resistant bike locks available at the moment.
And although it’s significantly less resistant to angle grinders than the OnGuard RockSolid, as long as a lock requires more than 1 disc to defeat (and the Litelok X1 does), that should be enough to deter the vast majority of thieves.
It’s also a bit bigger than the OnGuard RockSolid, so will give you more locking options. It’s only slightly heavier. And it comes with a great frame mount!
So if you like the idea of the OnGuard RockSolid, but can find it a decent price, then the Litelok X1 is a fantastic, lower priced alternative. In fact, I like it some 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?
If you are concerned about the lower Sold Secure Pedal Cycle Diamond rating, or you just want a bike lock that’s even more angle grinder resistant than the OnGuard RockSolid, then the Hiplok D1000 could be a good option.
The Hiplok D1000 is one of the most angle grinder resistant bike locks currently available, and it’s exceptional all round security is reflected in the Powered Cycle Diamond rating from Sold Secure.
Like the OnGuard RockSolid, it’s a mini u-lock so, it’s nice and compact for transport.
However, be aware that is much heavier (and heavier than the Litelok X1, too).
There’s a fabric, frame mountable pouch available now. And Hiplok are about to release a pretty nice looking, more conventional plastic frame mount shortly.
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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