The best bike lock for city riding is a rated U-lock, such as the ART-4 Abus Granit X-Plus 540, backed by a second, different lock. Match the rating class to your bike’s value and your insurer’s conditions.
This guide ranks locks by rated class and explains how to lock a bike so it is hard to steal. Scooter owners can read the scooter section here, then see what safety gear do you need for electric scooters for the rest of the kit.
Choosing a lock by rating class and insurer conditions
A security rating lets you compare locks by class instead of by thickness or looks. Schemes such as Sold Secure and ART sort locks into classes, and the ART classes are the ones that retailers and insurers quote most often in e-bike guidance.
According to a bike retailer’s guide to e-bike locks, most insurers require a lock certified ART-2 or higher, and ART-2 is often the minimum. ART-3 is recommended for high-end e-bikes. ART-4 is the top class and is often mandatory for speed pedelecs. The same guide warns that some basic locks open in seconds, so a lock with no rating is a poor bet in a busy city.
- Everyday bike, modest value: ART-2 meets the usual insurer minimum, so it is a sensible floor.
- High-end e-bike: step up to ART-3, as the guidance recommends.
- Speed pedelec or very valuable bike: choose ART-4, which may be a condition of cover.
Always read your own insurance conditions before relying on a lock. The guide notes that a lock below the required class can leave you without compensation after a theft.
Ranked locks for city riding
The order below follows the rated class given for each named lock, highest first. Within a class, practicality decides, because a lock left at home protects nothing.
Abus Granit X-Plus 540: the highest-rated U-lock
This U-lock is listed at ART-4, the top class. The retailer guide describes U-locks as extremely solid and hard to force, but less practical day to day. It suits a valuable bike that is parked in the same few places, where you can leave a heavy, rigid lock on the bike or at the destination. It is a weaker fit if you need to lock to wide or awkward objects, since the shackle is rigid.
Kryptonite Evolution Series 4: a chain with thick links
This chain lock is rated ART-3 and has 14 mm links. Chains in general are very robust and flexible, but usually heavy. The guide gives a 3 kg chain as an example that protects well but is not always pleasant to carry every day. This choice suits riders who park at varied street furniture and can accept the load, ideally with a bag or a frame mount.
Abus Bordo Granit X-Plus 6500: the folding option
This folding lock is listed at ART-2/3. Folding locks are compact and easy to carry, but slightly less resistant than a U-lock or chain. They suit commuters who carry the lock every day and park in busy, well-lit spots. They are the wrong choice for a high-end e-bike left for hours in a quiet street, where a higher class makes more sense.
AXA Absolute 9-110: a chain at the common insurer minimum
This chain is rated ART-2, which meets the usual insurer minimum. It weighs 2.5 kg and is described as robust. It suits a mid-value bike parked at a fixed home or work rack, but the weight makes it a poor companion for a rider who wants to travel light.
Frame lock: a complement, not a main lock
A frame lock (ring lock) is practical but insufficient alone. Used by itself it does not secure the bike enough, so always combine it with a second lock. Its real value is speed: it stops a quick opportunist at a short stop while the main lock handles the longer parking.
Comparison of the ranked locks
| Lock | Type | Rated class | Stated detail | Planning use |
|---|---|---|---|---|
| Abus Granit X-Plus 540 | U-lock | ART-4 | Extremely solid, hard to force | Valuable bikes and speed pedelecs; accept less convenience |
| Kryptonite Evolution Series 4 | Chain | ART-3 | 14 mm links | High-end e-bikes at varied parking spots; carry the weight |
| Abus Bordo Granit X-Plus 6500 | Folding lock | ART-2/3 | Compact, slightly less resistant | Daily commuters who value carrying ease |
| AXA Absolute 9-110 | Chain | ART-2 | 2.5 kg | Mid-value bikes parked at fixed racks |
| Frame lock | Ring lock | Not rated here | Insufficient alone | Quick stops, always paired with a main lock |
Figures and class descriptions come from a bike retailer’s e-bike lock guide.
How to lock a bike so it is hard to steal
A good lock fails if it is used badly, so the method matters as much as the class. Follow these actions in order, based on the same retailer guidance.
- Pick a busy, well-lit spot. Thieves prefer places where nobody looks. If you ride after dark, see best bike lights for night riding for visibility on the way.
- Attach the bike to a solid fixed point. A rack, post or other immovable object. A lock around only a loose item does little.
- Use two different locks. Different designs need different tools, so a thief must defeat both. A frame lock counts as one of the two but never works alone.
- Remove the battery for long absences. On an e-bike left for a long time, take the battery with you.
- Consider a GPS tracker. It does not prevent theft but helps recover a stolen bike.
Compare lock choice with the ratings above: the method reduces opportunity, and the class decides how long a determined thief needs.
Locking an electric scooter
The guidance above is written for bikes and e-bikes, but the method carries over to a scooter: fix it to a solid point in a busy, well-lit place and use two different locks. A chain’s flexibility is its supported advantage when the fixed point is awkward to reach around.
Choose the rating by how much the scooter is worth and what your insurer requires, and check those conditions before relying on any lock. If you are still deciding between the two machines, electric bike vs electric scooter compares them. A folding lock is the easiest to carry on a scooter, but the same trade-off applies: it is slightly less resistant than a U-lock or chain.
Frequently asked questions
What is the best type of bike lock for a city?
A U-lock rated ART-4 is the toughest listed here, while a chain offers flexibility at the cost of weight. Whatever the type, pair it with a second lock.
Are folding locks as secure as U-locks?
Not quite. Folding locks are compact and easy to carry but slightly less resistant, so they suit short stops in busy places better than long, unattended parking.
How do security ratings like Sold Secure work?
They sort locks into classes so you can compare them. In the ART system, ART-2 is often the insurer minimum, ART-3 is recommended for high-end e-bikes, and ART-4 is the top class.
How should you lock a bike so it is hard to steal?
Fix it to a solid point in a busy, well-lit place and use two different locks. Remove an e-bike’s battery for long absences.
