Bicycle Lock Review

No bike lock is impenetrable

According to the FBI, more than 300,000 bicycles are stolen in the United States each year. Although statistics don't indicate how many of those bikes were locked, experts speculate that most stolen bikes are left unlocked and represent a crime of opportunity -- a thief sees a bicycle unlocked and makes off with it in seconds. Bike locks, especially the best-rated locks, can be an effective deterrent against theft, but no lock is unbreakable.

For theft prevention, reviews indicate that the best bike locks are U-locks or chain locks. U-locks have a thick steel shackle that is attached to a crossbar with a keyed lock. Chain locks have tough links that are typically attached with a small disc lock, requiring a key to open. Both of these types of bicycle locks can effectively secure your bike, but U-locks are usually lighter and more portable than chain locks. Most U-locks include a mounting bracket so you can carry it on your bike frame while riding.

There are also numerous cable locks on the market, but you won't find many experts who will recommend these locks. Chain locks use steel cables attached to a combination dial or keyed padlock. A cable lock is certainly better than no lock, but they can be easily broken in seconds and provide little security in high-theft areas. Still, cable locks can be good secondary locks when used in conjunction with a tougher chain or U-lock.

Some of the top-rated bike locks, like those in the Kryptonite New York Fahgettaboudit line, can be expensive. Still, experts say you shouldn't think twice about investing at least 10 percent of your bike's value in a good lock -- or multiple locks. Many cyclists use a large chain or U-lock to secure their bicycle to a stationary object, while using smaller U-locks or cables to secure wheels and seatposts. If you live in a high-theft area, you may want to invest in several locks for maximum security.

While reviewers generally agree that hefty U-locks give you the best chance of avoiding bike theft, even these bike locks aren't perfect. In 2004, it was discovered that many U-locks with cylindrical keyholes -- including pricey locks from Kryptonite -- could be quickly picked with the empty barrel of a Bic pen. The New York Times reported that several other brand-name bicycle locks and several locks for vending machines, security panels and other devices were also vulnerable to a thief armed with a pen. Even today you can find YouTube videos demonstrating the problem. Kryptonite reacted quickly with upgraded replacements, recalls and new bicycle-lock designs, but they still caught a lot of flack.

We found a number of comparative reviews of bike locks, but many of these are outdated and conducted outside the United States. Tests by the U.K.'s Cycling Plus, Australia's Choice and New Zealand's Consumer magazines are helpful, but they typically include a number of bicycle locks not available in the U.S. The best American tests come from Men's Journal and Slate.com, although the Men's Journal test is more recent. Slate.com's Scott Elder tries to break nine bike locks with a crowbar, 30-inch bolt cutters, a hacksaw, three types of blades and "my trusty claw hammer." Similarly, Men's Journal tests five bike locks using a variety of tools, rating each lock on security and usability.

We also found good -- but not comparative -- reviews in publications like Bicycling magazine and BikeRadar.com. These sources test locks for strength and durability, but they don't compare the locks to others on the market. Owner-written reviews are also helpful, especially at Amazon.com. Many bike locks attract at least a dozen reviews on Amazon.com. Other review sites, like Buzzillions.com or TotalBike.com, have a few reviews but are far from comprehensive.