Price: £54.99
Weight: 815g (shackle), 330g (cable)
Shackle Thickness: 13mm
Locking area: 140 x 105mm
Cable Length: 120 cm
Security Certification: Sold Secure Gold
There’s nothing worse than returning to your bike after a long day at work, only to discover it’s not where you left it. For commuter cyclists in urban areas, keeping their mode of transport safe from prying hands is absolutely crucial, and investing in one of the best bike locks is a priority for many.
Designed with commuters in mind, the Abus Ultimate 420 + Loop Cable promises compact and reliable security at an affordable price, but is it one of the best budget bike locks you can buy?
According to the brand, this D-lock and cable combo is ideal for securing your ride on busy streets, and with bike theft a constant concern, it claims to be tough, versatile and easy to use. So we spent some time putting it to the test, assessing its suitability for the busy commuter cyclist who’s probably already lugging around a backpack or pannier bag and needs something compact, lightweight and dependable that doesn’t break the bank.
Read on for a detailed look at its design quality, portability, security offering and whether we’d recommend it for protecting the best commuter bikes from theft.
Design and aesthetics
The Abus Ultimate 420 is a traditional D-lock that comes with a 120cm Loop Cable for a 2-in-1 locking combination. It balances a compact and minimalist design with a bold red shackle that, according to the brand, is intended to scare off opportunistic thieves. It comes in two sizes — 140mm and 230mm — with the 140mm version tested here being particularly portable and well-suited to urban and commuter cyclists.
The shackle is made from 13mm thick hardened steel and sheathed in a rubberised exterior coating to protect your bike’s paintwork. This extra layer brings the total diameter up to 17mm and contributes to a thicker and more robust appearance, which you’d expect to see on more expensive and higher-security locks.
The double locking mechanism secures the shackle at both ends as it slots into a chunky locking cylinder with a keyhole at its centre (notably lacking a weatherproof cover). The result is a compact D-lock that appears to be packing even more steel than it actually is. This, combined with the bright, aggressive red colouring, acts as a visual deterrent and clearly demonstrates Abus’ focus on creating the illusion of a much more robust lock than the price tag affords. This isn’t a comment on the actual security the lock provides, though, which we’ll come to shortly.
Despite its relatively chunky appearance, the Ultimate 420 weighs 815g and feels light in the hand. It’s very easy to carry, whether you choose to use the included bracket to mount it to your frame, or tuck it into a pannier or backpack. The Loop Cable weighs an additional 330g and doesn’t come with any kind of carrying solution, but it’s malleable enough to wind up and store in a bag.
Security
While Abus has put a lot of thought into visual deterrents, it doesn’t skimp on the actual security the Ultimate 420 can provide. It’s got certifications coming out of its ears, including a Sold Secure Gold rating in the UK, plus several European awards, like the Swedish SBSC and Danish Varefakta.
The 13mm steel shackle, while not the thickest on the market, is enough to resist common tools like bolt cutters, and is bolstered by a double-locking mechanism that makes it more resistant to prying or twisting. It’s this form of protection that makes me more inclined towards the shorter 140mm shackle, as opposed to the longer 230mm version. While a longer shackle can offer more versatility in terms of anchor points, the shorter option leaves less room for leverage.
Meanwhile, the cylinder lock is high quality, adding to its overall security, and has been designed to resist picking. It even carries Abus’s ice spray seal, meaning it’s been tested to withstand extreme cold attacks. All of this, combined with the 120cm Loop Cable, is designed to keep bikes safe in busy urban areas. The cable makes for a more versatile approach to locking up, since it allows you to secure your front wheel to the frame and rear wheel, as well as to an anchor point. I’ve always been told that it’s better to combine two different lock types to deter opportunists, as it requires them to have more than one tool and approach, and therefore takes a little longer. Still, it is worth noting that cables in general don’t provide the same resistance as a D-lock, so while it’s an effective visual deterrent for most chancers, the complete combination is unlikely to stand up to someone with an angle grinder or similar bank of power tools to hand.
With that in mind, the Abus Ultimate 420 + Loop Cable will suit most commuters locking up during the day in areas with a medium level of theft risk. I wouldn’t recommend it for overnight storage in a high-risk area.
Performance
Anyone who’s used an Abus D-lock before will be familiar with the simplicity of their use. Mounting the Ultimate 420 to a bike frame is extremely quick and easy to do, thanks to a well-designed bracket that comes complete with spacers to accommodate a variety of tube diameters. It only takes a few minutes and a Phillips screwdriver to secure it to the seat tube and ride off.
Something to consider is that the bracket actually situates the lock on the outside of the frame, which means there’s a chance it’s going to rub against your leg as you pedal. If you ride a larger-sized bike, you’re going to have more choice about where to place it, and potentially not need to worry so much about this. However if, like me, you ride an XS frame, you’ll be more limited in placement options. Without giving up my second bottle cage on the seat tube, I was only able to mount it just beneath the top tube, which meant the lock would come into contact with my left leg as I pedalled. It wasn’t the most intrusive thing in the world, and after I quickly got used to it being there it didn’t bother me as much as I thought it would, but it’s worth considering if you’re looking for a more streamlined option. On the plus side, if you do decide against frame mounting, the lock is small and light enough to slip into a bag without adding too much weight or bulk.
For the purposes of this review, I kept the lock mounted to my bike frame and carried the Loop Cable in a backpack. Despite a slight looseness when attempting to shake the bracket by hand, the Ultimate 420 is mercifully silent while you’re riding. Perhaps my leg held it in place and prevented it from rattling while the bike was in motion, but either way, I was grateful for the quiet.
In terms of everyday usability, it is incredibly intuitive: just unlock the Ultimate 420 with the key, detach the shackle and cylinder from the bracket, thread the Loop Cable through your front wheel and frame, around your anchor point, and pop one loop through the other to cinch it all tight. Then thread the cable loop onto one of the prongs of the D-lock shackle and secure your rear wheel to an anchor point through the frame’s rear triangle. This way, all the important parts are secured with a mixture of two different lock types.
The cable is flexible and easy to work with, and though it provides an extra layer of security, I’d once again caution against relying on it alone in higher-risk areas; it’s better suited as a secondary deterrent for lower-risk situations.
The shackle’s compact size is a real asset here, as it keeps everything close to the anchor, reducing the space available for a thief to apply leverage to pry it open. With a locking area of 140 x 105mm, it fits snugly around standard bike racks like the Sheffield stands seen in the photos here, making it really suitable for built-up areas with lots of dedicated bike parking. However, it is less likely to work as well with thicker or unusually shaped anchors, like lampposts or square poles. Be sure to check against the provided measurements before buying, to check that it’ll be compatible.
Engaging the lock feels smooth and solid, and the high-quality cylinder allows the key to turn with precision and minimal effort. I found the lock to operate without sticking, even in cold and damp conditions, making it a reliable contender for regular use. However, it’s hard to ignore the lack of a cover for the keyhole, which could leave it vulnerable to weather damage in the long term.
Verdict
Overall, the Abus Ultimate 420 + Loop Cable delivers well as a commuter-friendly lock. It’s compact, rattle-free when mounted, and easy to use on the go. While it’s not designed for overnight storage in high-theft areas, its portability, easy setup, and secure lock mechanism make it a great choice for daily rides and daytime use in medium-risk environments. Commuter cyclists in need of a reliable and certified lock to keep their insurance providers happy will find it an excellent option.
However, it’s not perfect. It comes with some drawbacks like its rigid design that limits it to narrow anchor points, and the lack of a keyhole cover that exposes the inner workings to nasty weather conditions.
If you have to get creative with locking up in exposed areas, it may not be your best bet, but if you’ve got regular access to a Sheffield stand or equivalent that’s shielded from the worst of the weather, you’ll be golden.
