After investing in a tricked-out mountain bike or getting a good deal at a garage sale, you'll want to be sure you can ride your bicycle around town without fear that it will be stolen. When buying a bike lock, you'll want to consider prioritizing different features of each lock, possibly including strength, weight, ease of use, shape and overall design. Depending on the size and value of your bike, as well as where you'll be leaving it, there is a wide variety of locks to meet your needs.
One important thing to consider when choosing a bike lock is who will most likely steal your bike. On a busy college campus, for example, thefts are often crimes of convenience when someone spots a bike that hasn't been locked at all. However, if you ride your bike around an urban center for commuting, people might have specialized equipment such as crowbars, lock-picks and hacksaws that are no match for weaker locks. Leaving your bike in the same public place for hours at a time, as opposed to a few minutes while you rent a DVD, gives someone even more time to take advantage of your lock's particular weakness.
You'll want the best possible bike lock you can afford, since its cost is always less than that of replacing a stolen bicycle. Most people recommend spending about 10% of the value of your bike on its lock. If your bicycle is very precious or expensive, try a combination of several locks when leaving your bike in an unfamiliar area or for an extended period of time.
The bike lock mechanism is composed of two different parts: a structure that fastens your bike to itself or to a stationary railing and the lock itself, both of which have strengths and weaknesses. Some bike locks use combinations, like lockers. While combinations seem secure because they aren't easy to guess, these kinds of locks are usually strapped to a thin metal chain that is easy to clip apart with bolt cutters. Then again, you don't have to worry about losing a key if you are prone to forgetfulness, and they are lightweight enough to carry everywhere. Combination locks will work as a visual deterrent against people looking for an easy theft.
For many people, weight is an important consideration when selecting a bike lock. Whether you're training in mountain biking, cross-country marathons, or just visiting a friend, the last thing you want is a twenty-pound weight strapped around your frame slowing you down. There isn't a precise correlation between weight and strength, however. A special steel, called tool-hardened steel, will at least be as strong as many saws and cutters without being overly heavy.
Lifelong bicycling enthusiasts may consider saving up for a heavier duty bike lock, such as a U-lock or an O-lock. These locks fit through your frame, wheel, and a stand or pole. Their unique shape makes it harder to pry them apart with crowbars or saw through them. Available in different sizes, you should select one that fits snugly around the bar of your frame.
Some manufacturers offer a warranty along with their lock that may partially reimburse you should your bike disappear. Of course, nothing is absolute. Recently, it came to the attention of concerned bike riders that some types of very secure locks can in fact be opened with the plastic shaft from an ordinary pen. Keep in mind that while every bike lock has its weakness, there are many issues to consider when buying the right one for your bike.