To find the best bike lock in the world, we started by examining the literature. We scoured the bike lock market to find the highest performing and most popular models from over a dozen manufacturers. We bought the best models and sent them to our testers, who regularly commute on two wheels to work, community league nights, compete in cycling events, and generally find happiness on a bike. After receiving the locks, our lead tester rotated through the locks on a daily basis over the course of three months. We locked and unlocked each model countless times to various racks, poles, trees, fences, and posts. We also installed each mount more times than we wanted to keep track of. To receive a diverse range of opinions, we passed out the locks to fellow cyclists, too.
We assessed all models across four pertinent yet mutually exclusive performance metrics, each weighted according to significance. Security was weighted the most at 30% of the total score. Although security is the underlying point of these products, "security" doesn't measure how the extra four to five lbs. feels on your lower back or legs after long commutes, nor how it feels to fiddle with the locking mechanism for two extra minutes at the bike rack while wind, rain or snow is spitting in your face. Besides security, we also assessed each model on its portability (25%), ease of use (20%), and versatility (20%). Below we describe how we approached each metric.
In this metric, we first considered the security rating of each lock earned from independent security rating agencies such as Sold Secure and Foundation ART. These agencies have experts investigate the integrity of each lock and how easy they are to compromise. These scores weren't revered as golden but served as a launch point.
Our next step (although we carried this out at the very end of the testing period, for obvious reasons) was to destroy every lock systematically. After assessing the estimated weak points of each model, we started with basic, inexpensive hand tools that are commonly used. First up were wire and tin snips, and then a three-pound hammer, which are all easy for bike thieves to carry and to conceal. Next, we upped the ante with bigger and more destructive hand tools that are also popular among bike thieves, namely a pair of 36" bolt cutters and a 12" hacksaw. If models could not be broken with hand tools, we switched to power. A cheap electric angle grinder with a cut-off wheel was the tool of choice. We kept track of how long it took to "steal" each bike with an angle grinder.
Ease of Transport
We weighed each model on our scales to have some quantitative data to work with. The weight measurement is that of a lock and one key. Because not everyone opts for mounting the lock on their bike frame and because the frame mounts all weighed within a few ounces of each other, we didn't include those weights in our measurement. Other considerations within this metric include how well they can be carried on your person and in a saddleback, jersey pocket, backpack or messenger bag. Lastly, we judged the included frame mount, if any, assessing its ability to adapt to different bikes and frame placements. If the mount caused the lock to rub against our legs, impede pedaling, or allow the lock to rattle, we docked points.
Ease of Use
How easy a lock is to use may influence your willingness to use it when you need it. We opened and closed each model over and over again to check for sticky locking mechanisms. Our testers tried each model on a multitude of bike racks and other immovable structures to see how easy they secure to various lockup points. We investigated helpful and annoying features, such as keyhole covers, keys with integrated lights, and key shape. Finally, we also valued how easy it is to install the frame mount.
To test versatility, we sought out how much of a bike could be secured using the lock. Some models are only large enough to lock up the frame and one wheel. Other locks were able to secure the saddle, both wheels, and frame to an immovable structure. We also removed the front wheel and positioned it next to the rear wheel to see if securing both wheels was possible in this manner. We took into consideration different bike sizes and wheel widths as well, from skinny road bikes with skinny tires to robust mountain bike frames with fat tires. The more parts of the bike a lock could secure, the higher the score in this metric. We also took into consideration how well a lock performs when locking up other items, such as dirt bikes, motorcycles, bike trailers, and other expensive items found in a garage or backyard shed.