Kryptonite Evolution Standard Bike U-Lock, Heavy Duty Anti-Theft Bicycle U Lock, 14mm Shackle with Mounting Bracket and Keys, High Security Lock for Bicycles Scooters

Got two sets of them Mini-7 and Series 4. Both are brilliant nothing else to say, locking device is working very well. Somebody already tried to cut the lock!! It only has bin week. But guess what, they litterally only scratch the surface of it, probably after trying for a bit they realised that it's not the lock to cut!! Couple of thing to point out 1. Small bracket which you can attach to your bike and then just hang the lock on is very cool, plastic but lightweight and sturdy enough.. at least you dont have to hang the lock in the odd places while cycling! 2. There was a 3 key set and one of them came in with the light on the key, this is small but very cool feature, actually does help to open up the lock in the dark.! It's quite heavy thou, but this is the only way to protect your bike in town.... You can easily remove it and store it when cycling out!

This a very sturdy bit of kit. I'd just bough a £500 ish MTB and decided that my cable lock alone wasn't quite gonna cut it. I turned to the internet and quickly found Kryptonite to be a brand with a good reputation. After deliberating what price point I should by, I turned to this. My first impressions were bloody hell this things heavy although I've never had a U-Lock before. It comes with a few keys, one of which is bulkier than the others as it has the addition of an LED light which I have to admit I do find somewhat useful especially in the dark. The keyhole itself is covered by an orange plastic cover which stops dirt getting in. The lock itself is very sturdy and would require an angle grinder to cut through. My one complaint however is that the actually heavy U-Lock piece itself soon becomes hard to separate from the orange locking piece. This is certainly an issue, but it is combatted with a bit of WD-40 wiped onto the locking parts of the U-Lock as well as where it sits in the orange locking mechanism piece. This never caused any real trouble for me but I can certainly see how other reviewers locks have become jammed. Overall a very sturdy lock which has and continues to serve me well in conjunction with a cable lock. A lock like this is a must have for anyone who wants to keep their bike safe and taking it's small fault into account, I'd certainly recomend it to you.

The lock works quite well but make sure you lubricate the insides to keep it working functionally. It develops rust inside lock mechanism after a couple weeks being exposed to intermittent rain. The main issue is not with the lock itself but the lock holder which attaches to the frame. I've owned this lock before, and they have since updated lock holder. The previous style worked perfectly for about 10months then the failed completely as the ratchet teeth slipped through the clip. The new version of the lock holder seems to avoid this problem, however it has slipped loose on me a number of times requiring me to remove it completely and reattach it. I think it's important to lubricate the latch mechanism where the lock slips into the holder since the extra force required to remove it unlubricated loosens the holder prematurely. The other issue with the lock holder are the pictures on the instruction manual showing all kinds of configurations of lock positioning, none of which work except for attachment to the top cross bar (letting the lock hang down or the back down tube, in which the lock will rotate around and with gravity. It doesn't get in the way in this position, though.

Best bike lock i have bought to date (i have bought at least 6 in the last year). I have 3 locks for my bike because I live in London, and its better to be safe than sorry, and this is the best one I have. I tried a cheaper Kryptonite but it wasnt the same. I now have two of these ones. Also, it fits around the wheel + frame when locked, most tend to fit just the frame.

Checked a lot of reviews and only thing that was negative was that the flexframe bracket sometimes moved. Was sure that was just down to poor fitting so ordered anyway. Removed from packaging and tried to slide lock into flexframe bracket. It would only go half way in and then locked solid with friction. Thought that probably once bracket was tightened on the frame things may loosen up but wasn't convinced. ( That was a big mistake. Should have just put it back in box and sent it back). Fitted bracket which was easy and secure and then tried to place lock in mount. It was just the same and halfway in started to tighten and then solid. ( mistake no. 2. Again should have just took it off and sent it back) but no, thought it just wants a little fettle of the aluminum piece. After 1 1/2 hours of filing and cursing it finally slid all the way in only now with all the in and out I have obviously damaged the plastic retaining clip. Had no choice but to try as bike off back to uni with son in the morning. Now got a wonderful £50 paperweight!

This lock is pricey but excellent! The included mount attaches firmly to the frame and stays completely secure while riding. The size is just right—not too small to lock both the frame and wheel, but not so large that it’s hard to carry or fit in my medium-sized frame. The key operates smoothly with no sticking or hassle. Highly recommended.

And if it does not, why not? This lock is (so) heavy, (so) substantial that requires 'guns of steel' (that's biceps, by the way) to use it everyday. Truly a secure feeling lock that should ideally combined with a non-Kryptonite lock to thwart (or at least delay) those pesky bike robbers. The keys (three in total) are firm and solid (but read the instructions: "don't be hasty in twisting the key too quickly"), and the single key LED night-light is a nice touch. I cannot judge on how well the lock's frame mounting/housing works as I have a water bottle attachment in the most suitable location. The lock comes with a UK warranty (lifetime) and an option to either apply for a free key registration or a free £1000 protection for one year (if stolen you are required to submit a UK Police Crime Number, the lock, receipt for bike purchase, etc. to the manufacturer). This is may be useful for some people though a deterrent of a large Official sticker (visible on the frame) and UV permanent marking from the UK Police's free BIKE REGISTER program may be even more useful. Overall, this Kryptonite Evolution Series4 Flex Frame U-Lock is the peace of mind that I was seeking below £35.00 (at the time of purchase on Amazon.co.uk).

Very good. Highly recommended. ✅💯