We're not going to lie to you. No security system is foolproof, not even the best lock for road bikes or mountain bikes. With the right knowledge and proper tools, a thief could break it in the blink of an eye. The important thing is to do everything possible to make their job more difficult.
One of the best tips is to use two locks with different types and brands of mechanisms. It's possible that a thief could break one of the locks, but it will be much harder for them to overcome the second, especially if it is completely different from the first. This double security makes the task more complicated and is more effective than trusting a single lock, no matter how unbreakable it may seem at first glance. 
Main types of bike locks
Aside from particularities, there are four main categories of bike locks: U-locks, folding articulated locks, chain locks, and cable locks. Below, we analyze some of their features so you can choose the one that best suits your needs.
U-locks
We can say that the U-lock is the quintessential bike lock. This type of lock, with a design that includes a large shackle and a crossbar reinforced with the built-in locking mechanism, has been one of the most popular options among cyclists for years, both for mountain bikes and road bikes.
Its success is due to the fact that it offers an excellent balance between portability and weight, making it a practical option for securing your bike. In addition, many models come with a mount that allows you to easily attach it to the bike frame, which makes it easier to carry. U-locks provide a good level of protection, making them ideal for those looking for a secure way to protect their bike.
In general, U-locks deter opportunistic thieves, especially when used correctly to secure mountain or road bikes. These locks are not easy to break due to their robustness. However, to further increase your bike's security, it is important to keep the lock off the ground. This will make it harder for the thief to operate and prevent them from using tools to force it open.
A good tip is to fill the shackle as much as possible to prevent leverage attacks. A U-lock with a shorter shackle can help in this regard, although keep in mind that it will also make it harder to lock your bike. If you decide to use two high-quality U-locks, your level of protection will be excellent. We recommend using one to secure the rear wheel and frame, and another to secure the front wheel and frame of your bicycle.
It is true that the solid metal shackles that make up these devices make them less versatile compared to folding or chain locks. That’s why combining them with a second lock is an excellent strategy to protect your mountain or road bike in any situation.
Folding locks
If you want a combination of lightness, portability, and strength you can trust during long stops, a folding lock may be the ideal solution. Folding locks are the most portable on the market. Stored in their case, they take up little more than the palm of your hand, making them easy to carry. The strongest ones use 5.5 mm hardened steel plates. 
Due to their reduced thickness, these plates do not provide as much security as the shackle of a U-lock, but their wide and flat shape makes them resistant to almost all attacks.
Chain locks
If you’re looking for a lock for a bike that remains parked for a long time, a large and heavy chain with reinforced links is the best option. Combined with a strong lock, it provides the highest level of security for your bicycle. They are somewhat cumbersome to transport. The weight of the locks and reinforced links makes them substantially heavier than other types of locks.
A heavy chain with reinforced links offers an exceptional level of protection.
A chain lock is usually covered by a fabric sleeve to protect the frame. For the same reason, the U-locks we saw earlier have a plastic or rubber coating. One advantage of the chain is that it is adaptable and can reach any corner of your bicycle. Its shape also makes it difficult to attack with traditional tools. Try to pry a chain and you’ll see it’s not easy at all. They are also hard to attack with power tools and impossible to cut when the section of their links measures 16 mm or more.
Cable locks
Lightweight, flexible, and cheap. Cable locks are made of braided metal wires, hidden under a plastic coating. Most provide minimal security levels and you should only use them for short stops where your bike is not 100% unattended. It’s a fact that bike thieves specifically target these locks. Some reports suggest that up to 90% of stolen bikes they have a cable lock as a security measure. 
A combination of a U-lock with a cable lock is an excellent option for those looking to secure both ends of their bicycle in a light and efficient way. Cable locks for bicycles are usually very useful, as some come with their own locking mechanism, either with a key or a numeric combination. In addition, there are models with loops at each end, designed to be used together with other types of locks.
When choosing what to secure on your bicycle, it is recommended that you focus on protecting its most valuable components. For example, you can use a cable lock to secure the front wheel, while a U-lock or a folding lock may be ideal for protecting the rear wheel and the frame. However, it is important to remember that a cable lock should not be your only security measure, as the internal metal strands can be easily cut with bolt cutters.
How to lock your bicycle
Well then. Having seen the types of locks, let's move on to action. It is of little use to have a bomb-proof device if you are unaware of some basics before leaving your bike alone and in plain sight of everyone. We share with you good and bad practices that you should keep in mind for greater security. They are not a panacea, but they help.
Good practices when locking your bicycle
- Always choose a busy place to park your bicycle. Thieves do not like to act in public. Look for a place where there are many more bicycles and place yours in the middle, never at one of the ends.
- Always tie your bicycle to a fixed point, such as a bike rack or similar. Make sure that neither the bike nor the lock can be released from the anchor point without the use of force.
When locking your bike, try to do it in a busy place where there are more bikes parked.
- Use a quality lock for your bike and secure the rear wheel and the rear triangle of the frame to the anchor point.
- Whenever you can, use a second lock to also secure the front wheel (ideally, also the front part of the frame). For a thief, it is easy to remove the wheel and take it away.
- If you use several locks, try to combine different types (for example, a U-lock with a chain lock; or a key lock with a combination lock). The vulnerabilities differ and the work for the thief piles up.
- Try to make it as difficult as possible for thieves. When securing your bicycle, try to keep the locks away from the ground. This way, it will be more difficult for them to use leverage with bolt cutters or hammers. Also, fasten the locks as tightly as you can around the frame. Leaving too much slack makes the thief's job easier.
Bad practices when locking your bicycle
- Avoid locking your bicycle only by the front wheel. The thief can release it and take the rest of your bike in a matter of seconds. A solitary front wheel tied to a bike rack is a far too common sight.
- Do not lock your bicycle next to another bike either.
- Also avoid locking your bike only by the frame. You will leave too much free space inside the lock, making it more vulnerable. In addition, your wheels will be unprotected.
- Finally, before leaving your bike, make sure your locks are properly placed and securely fastened.
Tuvalum Team
