Folded, U-lock, and Chains, Oh My!
Most bike locks are categorized into four types: U-locks, chains, folded, and cables. Some security devices even combine two of these types. They differ regarding the level of security they provide, versatility, and ease of use and transport. Your choice depends on what level of security is necessary to deter theft in the areas you'll be leaving your wheels, but also consider how easy the lock is to use and whether you'll lug it along with you.
These are comprised of hardened steel molded in a "U" shape, and they are usually covered in rubber or plastic to protect the paint on your bike and reduce rattling while riding. The two ends of the "U" (the shackle) connect to the locking mechanism, a crossbar that closes the "U" into a "D" (and is opened and closed with a key or a combination dial). The most secure U-locks have a tight dual locking system, whereby if the "U" is cut with a portable angle grinder (or another power tool), the ends are still locked tightly. This means that there won't be much movement in the bar ends if it is cut through. In this case, the bike thief has to make two cuts to get it off the frame or bike rack. Hydraulic bottle jacks are also employed by criminals to bust U-locks, though less common. Less expensive models and versions with a "bent foot" shackle design take one cut before they are pried apart. In general, this type of lock is going to take a committed or professional bike thief with semi-sophisticated tools to be compromised.
These consist of a steel chain with a sheath to protect your bike's paint. The ends are connected via a padlock of sorts. The variation in security here has to do with the thickness of chain and quality of padlock. A thick chain of hardened steel, with smaller gaps between the links, and a top quality padlock or disc lock is the toughest chain to break. Chains can be broken by torsional force, so a small gap between the links leaves little space for the insertion of a lever. If a thief has the right tools, however, it takes one cut of the padlock to defeat a chain lock. Chains are flexible and have a large diameter, which makes securing them to immovable structures easier. However, they tend to be bulky and weigh more than other security devices.
The most unique design belongs to folding locks. They are made up of multiple steel bars connected by rivets that allow them to pivot independently of each other. This provides much more flexibility than rigid U-locks, which is most useful when the structure you're securing your bike to is abnormally shaped. This type of lock is excellent for easy transportation because they weigh much less than U-locks and chains and they fold up into a compact size. They won't weigh you down or take up tons of space in your messenger bag. The main drawback is the level of security they provide, which falls in the low to middle of the range.
These are made of twisted or braided steel with a coating of rubber or plastic, anywhere from two feet and up in length. The ends connect in a lock (sometimes connect with hinges while other cable ends are secured firmly inside the lock). Variability within this category includes cable thickness, lock strength and type (combo or key), and if the cable is coiled or non-coiled. Additionally, cable locks with a higher number of braided wire strands are the strongest, as they are tougher to cut than cables with fewer braided strands. Cables tend to be lightweight, with the coiled versions being the simplest to transport, either in a bag or wrapped around your bicycle's frame. Their large diameter and flexibility also give them more versatility in securing your wheels to immovable objects. Cables are the quickest and easiest to cut through with simple and inexpensive hardware. As a result, we rarely recommend them for lockups that last more than a few unsupervised minutes, and we strongly caution against using them for overnight lock-up unless you live in an extremely low crime area.
When Should You Use a Bike Lock?
Some of you reading this are rolling your eyes; of course, you should always use one, duh. But it's not quite that simple. If you grew up in a small town, you probably don't remember locking up your 16" bike at school because you just didn't. Bicycle riders that go on a few rides a month and don't leave their bikes unattended probably haven't thought too hard about securing their bicycles because they haven't had to. Unfortunately, bike theft is something that all bike owners should take preventative action against (the alternative, if it happens to you, is a huge bummer). Choosing a lock is just as important as choosing a saddle and used as often. That said, we want to encourage you to find the perfect fit; a bike lock that suits the security needs of your neighborhood and one that makes it easy to form the habit of using.
Although style of lock and level of security sometimes become linked in people's brains after talking to the salesperson at a bike shop, there are lots of styles out there that come in varying degrees of security. So we say choose your transport style first, and then your security level because it is more probable that you'll like (and thus use) your new lock. The aspect first aspect of style to think about is where on your bike or person you'd want to carry your new lock.
On the Frame
If you're new to the biking thing and you are using your bike to commute, we recommend mounting your bike lock to your frame. There are many types of locks that include an easy to install (and if you buy it at a shop, they might install it for you) bracket that mounts onto your seat post or another part of your bike frame that you then clip your lock into while you ride. The frame absorbs the extra weight of the lock and, with correct installation, you shouldn't notice it much.
The 3.96 lbs of the Kryptonite New York Standard U-Lock felt balanced and effortless when attached this way, even after a long commute. Folding locks are much smaller, taking up less space on the bike frame, and also weigh less. Other ways to carry the U-lock style include securing it to your top tube and then dealing with the awkward one-handed re-adjusting as you're riding (not recommended). Another popular way is to bungee the U-lock to your back rack or front basket, which works well if you don't mind the extra time it takes to secure the lock. Lastly, you can loop it through your saddle stays at the back (if it fits) and let the lock hang above your rear wheel, but be sure it does not interfere with your tire.
Lightweight cable combo locks like the Kryptonite KryptoFlex also clip on to your frame. Cable locks also wrap around your seat post or handle bars. This is one of the greatest things about coiled (and non-coiled, to an extent) cables - they transport effortlessly. The lack of security they offer, however, stops them from being a viable choice in many areas (see the How Burly? section below). If you want a lock that attaches to your bike while you're riding, you are looking for a U-lock, a folding lock, or a cable lock.
On Your Person
Another option for transport style is carrying your lock on your person or in a bike bag (like panniers or a handlebar bag). This method opens your doors to all sorts of locks but is limited by the amount of weight you want to carry. U-locks range in weight but expect 3-4 lbs in your messenger bag or panniers. The Hiplok Original: Superbright is our favorite model to wear. It has a velcro strap that feeds through the backside of the padlock and back on itself, creating a belt to wear while commuting. Although chains with padlocks are criticized for being too heavy, the Hiplok model is roughly the same weight as a heavy-duty U-lock. An average sized person can likely handle 4 lbs wrapped around the hips better than that same weight in a backpack. That said, no one is going to want to throw the Hiplok over their spandex jersey before a training ride.
No bike lock is invincible. It's sad but true. There is a huge degree of variability when it comes to how quickly different products can be broken into, though. When it comes down to choosing a lock, first determine what level of crime you're up against. We like the way Kryptonite breaks it down in their How to Choose Your Bicycle Security chart. A rough estimate of crime level (ascending from more to less bike theft) is: "Major Metropolitan Area," "Metropolitan Area," "College Campus," "Suburbs," or "Rural Area." Next, you decide what the riskiest lock-up (in ascending order from most likely to be stolen to less risky) is: "Overnight Lock-up," "All Day Lock-up," "Couple of Hour Lock-up," or "Quick Stop Lock-up." For perspective, the riskiest scenario involves locking your bike up on the street in a large metropolitan area and leave it overnight. The least risky scenario is if you needed to lock your bike up for a few minutes in a small town.
If you live in a large metropolitan area, city, or college town, you need a U-lock or a chain with a substantial padlock. Within the U-lock category, some locks are harder to compromise. Kryptonite's line of New York U-locks like the Kryptonite New York Fahgettaboudit U-Lock Mini, the New York Fahgettaboudit Chain and Disc Lock, and the Standard are harder. Quality chain locks like the Hiplok Original are in a high/medium security category. Not quite the burliest, but impervious to hand held tools. Mid-level security U-locks are those like the KryptoLok Series 2, Cocoweb Armbar Combo, and OnGuard Bulldog DT.
What differentiates mid-level from a high level? Mid-level locks are rumored to pop open when an expert pry bar thief gets some leverage between the "U" and the frame, but it isn't an easy task. It does happen, however. High-security U-locks require two cuts with an angle grinder to break out your bike as opposed to the one cut needed for mid-security U-locks. This is due to the dual locking crossbar in the high-security locks that don't allow the bars to move, even if they are cut. Check out the reviews of locks in the Kryptonite New York series, as well as the ABUS Granit X-Plus 540, for more information on these uber secure dual locking U-locks.
Not in a city? If you are a rural resident that sometimes travels to cities, buy the lock that represents the highest level of crime that you're up against. You won't regret buying a Hiplok, which you carry around your waist for around town biking. Regarding general security, we only recommend a cable lock if you are certain that you won't need to leave your bike out on the street for long and that you only ride in a low crime area. If that is your user group, you've got super lightweight and easy to use options available to you. They are also inexpensive; the OnGuard Akita 8041 and the Kryptonite KryptoFlex 1218 Combo Lock run under $30. Between chain locks and cable locks are the folding locks. They can't be cut by wire snips but succumb to a variety of other hand tools.
How Much Should You Spend on a Bike Lock?
Throughout our testing process, we heard a lot about the 10 percent rule. That is, plan on spending about 10 percent of your bicycle's worth on a suitable bike lock. Although we think this is reasonable, be sure to consider the security guidelines above. The bicycle protection plans offered by manufacturers cover a lot more than that, however. For example, the $50 Kryptonite KryptoLok Series 2 comes with a $1,500 bicycle protection offer, and the $103 Kryptonite New York Standard comes with a $3,000 bike protection offer. Companies like OnGuard and Kryptonite also offer protection for motorized vehicles and locks used in the E.U.
This is good news for the folks on the more expensive side of the spectrum, but what if you own a $300 bike in San Francisco? You still need a U-Lock costing about $50, which is 17 percent of your bike's worth. View this purchase as insurance and think more about your security needs than the arbitrary 10 percent guideline. Additionally, think of the time, effort and money it costs you if your front (or jeez, rear - even costlier) wheel were to get stolen. For bike commuters, a stolen saddle or front wheel means having to buy another way home…then to work again. Buying a decent lock is worth the money, time, effort, and frustration of having all or a piece of your bike go missing.
Bike Locks If You Are Wearing Spandex
If you bike for training purposes, the last thing you want is more weight making you slower on the uphill. You've most likely considered weight as one of the major considerations when buying your training bicycle. This bike is also probably way more expensive than your town cruiser that you use to run errands or get groceries. So what do you do when you stop for a bathroom break or go into a store to get more water? Lightweight cable locks have a specialized use here. Locks like the OnGuard Akita and Kryptonite KryptoFlex fit in a handlebar bag or wrapped around your frame for quick stops. We have a sneaking suspicion that we don't need to tell you to be careful, but be careful! Don't leave your bikes out there for too long with only a cable to protect them.
Ok, I Bought One. Now How Do I Use It Effectively?
Once you decide on the product that's right for you, check to see if your new lock comes with an insurance policy. Some manufacturers offer insurance to reimburse customers in case of theft. However, you have a limited amount of time (sometimes just a week!) to sign up, so be sure to register it immediately. Also, if this is a major factor in your decision making, be sure to read the insurance policy. The stipulations tend to be rather strict. For example, some exclude customers living in New York, and some require you to send in the busted lock for inspection before any compensation is doled out. Furthermore, check to see how much money you stand to receive if your wheels get jacked — it might not be all that much. Once you've taken this step, file away your receipt and your registration info in a safe place to find it again in case of the unfortunate event of theft. The week you buy a lock is also the time to register your keys if the manufacturer offers a key replacement program.
Once you're ready to ride and use your new gear, be sure to do all your research on how to lock it up properly! Many bicycle thefts happen due to user error. It's important to know how to use your lock to maximize security. The most secure lock won't protect your biciclette if you use a weak locking technique. Furthermore, an improper locking technique might void your insurance policy in the case of theft. Here are some basic pointers to get you started on your quest to make your bike a tougher target:
How to Lock Your Bike
Secure as much of the bicycle as possible to the immovable object. If possible, secure both wheels and the frame. One option is to remove the front wheel and secure it along with the back wheel and frame to an immovable structure. However, if your lock doesn't allow this level of security, consider the value of each part of your bike, and lock the highest valued parts first. Always secure the frame first, then the rear wheel, then the front wheel. Never be satisfied by just locking up a wheel to a rack, as they can be removed quickly, leaving you to aggressively google "how to convert bike wheel into a unicycle."
Be sure to get a tight fit, filling up the inside of the chain, cable, or U-lock with as much of your bicycle as possible. This minimizes the amount of space that potential thieves have to use their tools, making it harder to break open. Also, if your security device has a keyhole, make sure it faces down toward the ground. It makes it more difficult to pick. Furthermore, take any removable items with you that want to return to, such as lights, saddle bags, water bottles, and even your seat if it isn't incorporated into the lock.
Where to Lock Your Bike
Always secure your bicycle to immovable objects or structures. Bike racks, lamp posts, and trees are good examples, as they are fixed in the ground or concrete. Some bicycle roof racks are also considered immovable objects when used correctly. Avoid using structures that are held in place by only a few bolts, such as "No Parking" signs. With a few quick turns of a ratchet wrench, the sign is removed, allowing the thief to slide the bike up and over the post.
Seek out areas where other bikes are locked up, and make sure that the area is well-lit if left out past dark. Lock up your bike on streets with a high volume of foot traffic. A lonely set of wheels on a quiet, dark street might attract the wrong kind of attention. Also, don't park your ride in the same spot every day, but keep changing it up. Moving targets are much harder to hit!
For more insight on proper bicycle security, check out this video from Art's Cyclery on the topic: