Kryptonite Evolution Standard U-Lock, 4x9 inches, Black, 3.5 pounds

I bought this lock when I first got my ebike, and came back to write a review after 4 years and was shocked to see all these 1-star reviews with people that can't seem to get their heads around:a) the limits of ANY U-lock (such as the fact it's rigid and thus not great for things like power poles)b) How to unlock the lock (hint: you push the key all the way in, and turn it)c) All bike locks are deterrents. If you park your bike in a dodgy place, or if someone *really* wants your bike, no lock will stop an angle grinder. At least this one will make it a pain in the ass.With those things in mind, here's a brief pro/cons on this lock after 4 years of use and 6000km of commuting on my bike. I haven't babied it, I've thrown it around and used it like a lock. It's been on the back of my rack all the time, and I've locked it up in some pretty sketchy places to find it always back and working, in the pouring rain, sleet and overnight. The key and locking system are still buttery smooth after 4 years, and although it's beaten up there is physically nothing wrong with it.PROS:+ Beefy security. It's heavy and hefty and a great deterrent. I've come back to see obvious scratches where people have tried to pick the lock, hack at it with some kind of saw and generally try to bend it (which left marks on my frame). I still have my bike 4 years later. I think the other reviews made the mistake of either parking their bikes not next to other bikes (always a good chance the bike next to you will be easier), or expecting this to stop a blowtorch and last for eternity. Locks are deterrents!+ Durability. I have locked my bike in and out of cover, under tarps and in the open rain for weeks on end. I also live near the sea, so I do get a bit more corrosion (I've been through two chains on my bike, for context). No issues with any part of the lock at all, including the key/locking system.+ Length - no, it won't wrap around telephone poles like a folding lock can. But as long as you understand that, it's a great size and length for most poles, bike racks and metal fences. It can be annoying give it isn't a folding/cable lock, but again the U-locks will be more secure than the former.CONS:- Hefty - this lock is a chonk. It's hefty and the frame mount is crap, so it has to live on my back rack. Honestly it doesn't bother me since I prefer the security but it does have to be said.- It's a U-lock - which means that it is rigid and it can't wrap around or through objects. I personally commute around the city where there are plenty of bike racks, metal fences or narrow sign poles for me to lock this up to. If you don't have that luxury, then get a chain or folding lock.- Key system was fiddly on first use: I remember when I first got this lock and I accidentally seized up the lock trying to unlock it. Turns out, it's really easy to half unlock the lock if you don't push the key all the way in *before* turning it. After a few months I got used to it, and I haven't had ANY of the durability issues I've seen from others in the past 4 years. I've always made sure to close the keyhole protector, and push the key all the way in before turning. No issues, but it was a slight curve- Not indestructible - All the photos and 1-star reviews I see are from people whose locks were cut through with an angle grinder or a very, very determined thief and a metal saw. Nothing will stop a determined thief. It's common logic to try and park in a very public, well-lit place, preferably next to some other bikes with crappier locks that are easier to steal. Thiefs are opportunistic, and so if the nice bike next to you has a shitty lock that takes less time to steal, they'll take it. I totally get it, people are mad that their bikes are stolen, I would be too. But that isn't the lock's fault - if you want a near-indestructible lock, get the NYC Kryptonite lock and carry an extra tonne of metal around, or get a frame lock too and multiple U-locks. For me, I just park in a sensible spot, locked to something metal and with the frame lock in my bike too. I've had several attempts on the bike, but no one got even CLOSE to cracking it. Remember kids, angle grinders aren't subtle or quiet. But if you park in a place with no one else around you, it will be.

Keeps my kid's bike safe- she already had one stollen at school. Too bad we can't have a lock that keeps medical insurance from stealing from us - since they do not pay their bills.

This bike lock is nice and sturdy and a deterrent for criminals. It takes a professional bike thief to saw this off, and stealing your bike with this on, it will attract a lot of attention. It's nice and long and attaches to the frame and wheel at the same time. It also has a great mounting system. You will not regret spending the money on this purchase!

Locks most set ups that include rim, frame, and object eg pole, stand. Balances toughness, weight vs practicality. NY locks heavy. Wish lock was an inch shorter, but this fits mtb bikes.

Had a series 2 before but Kryptonite made a big improvement on this lock creating a double bolt that prevents any twist after any type of attempted cut. The keyhole also seems tighter with a slide dust cover. Yep it’s heavy duty but I have no problem putting the lock in my backpack. I use this lock to lock up my front tire on my electric scooter. This lock is my primary lock but I also use a secondary lock which is a Kryptonite flex cable where I wrap around the frame with a attached padlock which is locked onto a stationary object. Basically this is a terrific lock. If your going to use this lock make sure you also use a secondary lock. I learned this while living in New York a few years back. In New York lots of cyclists use a primary lock and a secondary lock. Why...it’s called time. The longer the thief has to remove locks, the less his or her chances are of ripping off your bike. You can’t go wrong with Kryptonite. You get what you pay for.

I have had many bicycle stolen, and once I switched to this kryptonite, D lock, no more missing bicycles. I also use it to lock my scooters, and the quality is excellent. My children occasionally lose the keys, and I need to have replacement keys made at kryptonite and sent out. This takes a bit of time. One suggestion if you buy this is to simply order extra keys right away, because taking this off without keys is going to be very difficult

This lock should be recalled. It seems like it works fine when you test it over and over indoors when you are not actually trying to lock your bike, but as soon as I'm trying to use it to lock my bike outside? Forget it! I cannot for the life of me get the key to turn! It seems like maybe I'm just unable to push the bottom of the lock on all the way, is that why it won't turn? Just seems like it got progressively worse over the only 3 times I tried to use it, where the 3rd time I ended up having to carry my bike inside my gym because I couldn't lock it up. Plus, as others mentioned, this lock is pretty much limited to use with a bike rack, which is hard to find where I live, even at a shopping center. Trying one of those folding locks next so it is easier to lock to any old street post. I managed to lock this to a street sign post couple times, but it took me a long time to be able to get bike aligned right to the post in a way where I could get the lock around the bike and the post, even though my mtn bike is the smallest size the bike came in, very frustrating, and then to not have the key turn? Was so annoyed!!

I bought the "standard size." It's a bit longer than I expected, and not wide enough to lock my frame and rear tire at the same time, unless it is done at an angle, so it's good that it's a little long. Mounting the lock inside the frame would not fit because of a water bottle holder. I found on YouTube a company video showing how to offset mount the bracket and that worked well. That position was not mentioned in the included instructions and that is a fail. The mounting bracket does seem like cheap plastic, but is working well initially. Note that the free insurance mentioned is only for one year and they upsell you for up to 5 years on their website. But I did it, lol, $25 for 5 year protection for an expensive bike is worth it to me.