Bicycle lock types

What types of locks are there and which lock is safe? 
Security - when locking the bike - is of great importance. Which bike lock you choose depends on the area of use. Basically, it is recommended to invest 5-10% of the value of the bicycle in a lock.
There are 5 different types (categories) of locks:

• U-lock
• Chain lock
• Cable lock
• Folding lock
• Frame lock

Now there are some things to decide: Which lock suits me? Which bicycle lock has which advantages or disadvantages? Which bike lock is safe?

U-locks
One thing is for sure: U-locks are the most secure locks on the market, as they are made of hardened steel alloys in combination with a robust lock cylinder and are resistant to drilling and cutting. These types of locks are ideal for big cities and are a worthwhile investment. However, the size of the lock is limited and not variable, making them a bit more cumbersome to transport and usually equipped with a bracket. It is essential to ensure that the U-lock is simple, user-friendly and effortless to integrate into everyday life.

Chain locks
Chain locks are also very secure and flexible. They come with exposed chain or encased in a durable fabric. They are easy to transport and offer more possibilities to connect a bike. Thanks to the movable chain links, this type of lock can be easily placed around a wide variety of fixed objects, making it suitable for anyone who needs to use more unconventional objects to lock up while on the road.
A chain lock with a high level of security is locked via a cylinder with a key or number combination and offers little surface area for attack between the chain and the locking mechanism. Hardened metal and the thickest possible chain provide good protection against most attempts at tampering. However, chain locks are quite heavy and awkward to carry.

TIP: Note that not all chain materials are the same. To find out if your chain is safe, try sawing into it with a saw. The following two things can happen:

• The chain scratches - not a good sign! The chain material is not safe enough and can be destroyed with a saw.
• The saw slips off the chain - a good sign! The material of the chain lock is so robust that it cannot be destroyed with conventional tools

The more elaborate the safety technology, the deeper you have to dig into your pocket for a chain lock. This somewhat more expensive, but also very high level of security is not required for every bike, but is unquestionably worthwhile for valuable bicycles. Especially if you are often on the road in the city, you should not do without the secure theft protection of a good chain lock.
 

Cable locks
Cable locks are usually made of a steel mesh that is covered and protected by a tough plastic shell. This type of lock is available in many different styles and for every budget. The price varies depending on the thickness of the cable.
They are lightweight, flexible, take up little space because they spiral together after use, making them ideal if you want to secure your bike quickly. However, because of their weaker structure, they are also far easier to pick than chain or U-locks, for example. Often, a pair of pliers is enough to cut them. For securing in the garage or in places where the risk of theft is low, they are the right choice.
Cable locks are also great for supplementing a sturdy main lock. For example, many use a chain lock to secure the bike frame and an additional cable lock to secure the wheels or other accessories such as a helmet.

Folding locks
Folding locks have become increasingly popular in recent years. And for good reason, as they combine the flexibility of a chain lock with the security of a U-lock. Made from folding rigid plates, they also offer high cut resistance.
The clear advantage is that they're easy to carry: Although they're not always super lightweight, they take up very little space when folded. Folding locks come in many different lengths - so you can flexibly connect your bike to a wide variety of objects.

Frame locks that are mounted on the rear wheel (e.g. on city bikes) are best suited as basic protection for bikes that are parked for a short time in places with a low risk of theft. They are definitely not sufficient protection against theft, but prevent the bike from being driven away.
Frame locks should therefore definitely only be used in combination with another lock such as a chain lock or U-lock. Only then is your bike really safe.

To the lock selection 

How you can PROTECT yourself 

Deterrence and prevention are probably the most important measures. 

Keep the following tips in mind: 

• Always lock your bike to a fixed object. This prevents easy carrying away.
• Attach the lock as high up on the bike as possible and fasten it tightly to prevent leverage. This takes away the thieves' freedom of movement and makes it more difficult to use a pry tool. 
• Park the bike in a bright, visible and busy location. This is especially true for long-term parkers. 
• If you park your bike or e-bike regularly, change the parking location more often. This makes it more difficult for potential thieves to (re)find an object once it has been targeted.
• A secondary lock or smart lock increases security even more. 
• Quick-release skewers and theft protection unfortunately do not go together, because they are not only convenient for the user, but also for thieves. It is best to secure screws and axles immediately with special, coded lock nuts (e.g. Pitlock, Abus) or lock inserts (Hexlock). 
• As a preventive measure for bicycle theft, you should register and document your bicycle (with frame number and owner data) or have it coded by the police (GPS tracker). 
• An individual engraving can be helpful to quickly recognize your bike (recognition value). In any case, specific details should be photographed. Eye-catching tuning also makes it more difficult to resell bikes and thus makes bike theft less lucrative.
• Take out special insurance. 

What to do in the event of theft?