OnGuard RockSolid 8590

The OnGuard RockSolid 8590 is, as the name suggests, rock solid. The joint highest-scoring lock in our round-up, it was impenetrable by our crack team of angle grinder and bolt cropper-equipped thieves (aka Dave). And after testing it for a few months from a practicality perspective, I’d be hard pressed to find a better D-lock out there.

One of the perils of riding bikes (and leaving them) in the city, or even a bustling town, is the prevalence of bike theft. It’s a widescale problem that’s only getting worse with the increase in value of bikes – analogue and electric. And with thieves adapting to the various tools us cyclists use to try to keep our bikes safe, the market for an actually secure lock is bigger than ever.

Grinder proof

I’m always a bit dubious when a brand brings out something that’s ‘grinder proof’, almost tempting fate, like when the Titanic was labelled ‘unsinkable’. I’m sure criminal gangs will tell me nothing is unstealable, but what we can hope the locks do is slow thieves down or cause them significant annoyance so they decide it’s not worth the hassle of stealing our bikes.

The OnGuard RockSolid 8590, however, actually lives up to its name. And as Dave said in the road.cc lock-busting video, not only was it undefeatable, but he’d “never ever seen a cutting disc die so quickly”. So as locks go, it matches the performance of locks that cost £100 more and weigh 1kg more.

From a performance perspective, then, there’s not much there to dispute. It does what it says on the tin. But what about from a practicality perspective? What’s it like to live with?

Weights & measures

At 1.3kg it’s not the heaviest D-lock you can find – though that doesn’t detract from the fact it’s an extra chunk of weight to carry. However, in the grand scheme of things, I’d much rather carry a high-performance lock than risk losing my few-thousand-pound bike.

Like I said, though, it’s not the heaviest D-lock out there – the Abus Granit Super Extreme 2500 + USH 2500 mount, for example, weighs about 1.2kg more.

The lock is simple to use. You use one of the five included keys to unsheath the shackle from the lock and place it around your chosen frame part and whatever you’re locking your bike to. It detaches completely from the ‘D’ so you can easily manoeuvre the lock rather than having to worry about keeping the mechanisms connected as you fit it.

The design of the lock uses a 15mm steel shackle that sits within a patented ceramic coating, which OnGuard claims is designed to repel angle grinder discs. It also uses a double-rubber coating on the shackle to prevent marking your bike frame – which I very much appreciated as I did drop it a few times (through my clumsiness, not because it’s difficult for regular people to use).

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The only, and very small, qualm I had with this lock is the compactness of the space within the shackle. It fitted my road bike and a standard bike rack, but trying to get it to fit, say, a 42mm depth wheel rim, seat tube and rack was somewhat difficult. If I’m going to spend £200 on a lock, I’d probably want it to protect the entirety of my bike, rather than just the frame.

Then again, if I’m leaving the bike in such an area that might see my wheels or seatpost getting nicked, am I going to be using my pride and joy road bike? Probably not.

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So it’s a small and personal quibble that most people won’t think about. But if you are using it on anything other than a bike with what I would call regular-sized tubing, be aware that you might have to get creative with your lock placement.

Value

At £199.99 (and around £150 in sales), it’s a fair chunk of money to be spending. But when it comes to security, particularly Sold Secure Diamond rated locks, it’s not actually that bad.

From our lock testing, it appears that you need to spend about £150 as a minimum to get anything angle grinder ‘resistant’, and more if you really want to upset would-be thieves.

It’s also the lightest grinder-resistant lock we’ve had in to review, so all in all, it’s pretty difficult to beat.

If money is no object then the Abus Granit Super Extreme 2500 + USH 2500 mount at £280 might fit the bill. With the same Sold Secure Diamond rating, it’s a hefty D-lock (weighing 2.5kg) but comes with an optional frame mount, which our reviewer found quite handy.

If £200 is beyond your budget, the Litelok X1 at £149.99 is definitely worth consideration. It’s one of the lightest Sold Secure Diamond locks on the market, at 1.7kg, and comes with large internal locking dimensions.

Conclusion

Overall, the RockSolid 8590 is a near-perfect choice if you only have thin-framed bicycles. Sadly, I often have the luxury of testing electric bikes, which famously do not come with sleek, rounded down tubes, and the OnGuard’s limited space within the shackle means it doesn’t fit all types of bikes.

Otherwise, it’s an excellent lock, and has outperformed its price and weight point in our lock-breaking tests.

Verdict

Go-to grinder-resistant bike lock for cities, with Sold Secure grading and a decent price

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