Kryptonite New York Fahgettaboutit Mini Bike U-Lock, Heavy Duty Anti-Theft Bicycle U Lock, 18mm Shackle with Keys, Ultimate Security Lock for Bicycles E-Bikes Scooters

Superb built quality, going on nearly 2 years of use and it's not flinched once. Couple things to note; The plastic sleeve that covers the keyhole is rather flimsy and will likely come off with rough use. This does not affect the function much, if anything it makes accessing the lock easier. Otherwise, be mindful of the spacing your bike has! This is a VERY thick U-Lock and will have much less margin of error than something like a chain or wire-lock. All disclaimers aside, it is one the the sturdiest and safest locks I've used so far. Absolutely worth every penny.

I commute on bike daily and was looking for a lock that would allow me to lock my bike outside all day and not have anyone mess with it. I read the reviews of all the other locks and found example after example of situations where someone would break the lock. I was looking at the baddest, most serious lock there is. My bike, that I use for commuting, is only worth about $300...and this lock was close to $100. Seems not to be a good tradeoff but I look at it this way - I don't want the hassle and inconvenience of having to replace a bike that was stolen and for that it is worth the price. I had considered getting a beater bike that no one would ever steal but I really didn't want to give up reliability of a fairly new bike. This is a heavy heavy lock. It is also quite short (better to restrict leverage to break it). I had a hard time trying to figure out how to lock both the frame and rear wheel. I had to thread some of the spokes and the smallest rear triangle of my bike and then barely cleared the bike rack. I use a Krytonite cable lock for the front wheel and frame yet again. The point is to deter anyone from trying to deal with your bike and between the two locks I think I've assured that. The lock is a bit fussy about opening with the key. It has to be inserted all the way in but somehow gets caught up sometimes partially inserted. Again the two biggest issues are the weight (but I knew that) and the short size (have to be creative about figuring out how to secure a bike). Very well made. So after observing some people on BART (local commuter rail) I figured that I could lock the lock to my bike's front triangle as a DIY bike lock holder. This helps b/c in my backpack I was worried it was going to damage my chromebook.

First impression : "This thing is HUGE, HEAVY, how am I ever going to mount this on my bike?" Well, you CAN mount it. Use the Master Lock 8351D Smart Bracket . It works like a charm. You'll pay $4 on Amazon to buy the bracket. When you get it, take out the two screws from the shackle portion of the mount and throw them away. Then go to the hardware store and pay $1 for two M4 30mm bolts. If you use those to mount the hardware on the shackle, it works great. See my pictures, and more info on my review of the Master Lock 8351D Smart Bracket. The lock itself is heavily reviewed on the web - no need for me to repeat that here. BUT seriously consider WHAT you are going to lock your bike to. You cannot use this on a lamp post, and I have great doubts about whether it will work on a parking meter -- the lock is just too small. Check my uploaded images and you'll see the dimensions. I lock it to a very strong street sign at work, but it's a tight fit. You may want to measure your "fixed device" and bike frame and do the math before getting this, and make sure it will fit for you. If I get to try this with a parking meter I'll update my review. Highly recommended - but make sure to buy the mount, and check the size issue before you buy. Well, 1 year later I still have not had occasion to lock this to a parking meter - but I seriously doubt it will work. The parking meters here are just too thick for this to get around. I always pick a secure street sign at my workplace, and the few other places where I regularly ride. This just snugly fits around the post on standard street signs. Please research that issue carefully before you buy - make sure you can verify that it can get around whatever you need at your workplace or park -- it is a SMALL U-lock, but a great one. UPDATE 8/2/16 - six years later. By the way, my mount setup [Master Lock 8351D Smart Bracket.] 6 years later still is working without a hitch - that is definitely the way to go! slides right on the bike, and has never fallen off. And I've finally gotten around to getting a few pics showing the lock at a large handrail at work (1.5" diameter pole), and a signpost that I use every day for my lockup.

If you don’t want your bike stolen, get this lock! When I got this lock, it not only looked like a beast and felt like one, but it also had some serious weight to it. Totally worth every penny—super high quality! With the Fahgettaboudit lock, I feel confident no one can steal my bike. I bought it for my (Lectric) e-bike, and it works like a charm. I also love that it comes with multiple keys and that you can register them in case they’re ever lost or stolen. A quick note: if I’m going off-roading or don’t plan to use the lock, I take it off the bike because of the added weight. Overall, 10/10—love it and highly recommend it!

A great lock, certainly secure. But the lack of a mounting bracket is such a dealbreaker. It's crazy that I don't even sell an add-on for this

This is a seriously heavy lock offering top-notch security and peace of mind when locking up your ride. After a number of bike thefts occurred in my neighborhood (Boston) in which U-locks were cut or picked I decided to spring for the highest security I could get short of paying a retired linebacker to look after my bike. My first impression when this arrived was wow... this is heavy. Coming from a Kryptonite galvanized chain lock I thought I was used to carrying around a heavy lock. This weighs in around five pounds, and when combined with the 3/8" Kryptonite security cable I end up carrying around 6lbs in security equipment on daily rides. This may be excessively heavy for some riders and in most cases will require extra space in your backpack when riding around (there is no mounting hardware provided). As a result I do not ride with this when going for longer rides out of the city, though security is generally less of a concern on those rides. That said, on inner-city rides and when running errands in town I have complete faith that if I lock my bike up in a visible area it will be exactly where I left it when I return. While the price may be high for some, this kind of peace of mind is hard to put a price on. I also like the lighted feature on the main key that comes with the lock as it makes unlocking in poorly-lit areas much easier.

It’s really good, it’s really thick so it’s hard for people to steal ur bike which is the point, definitely heavier but worth the money, definitely recommend!

This beefy lock is a great choice for ebikes. My only complaint is that there's nothing that comes with the lock to mount it to the bike while riding.