900 Bike Chain Lock



Made for protecting your bike during long stops.
Highly resistant, high-security bike lock. Perfect for securing the frame and front wheel.


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Theft resistantHigh-security bike lock B'SECURE label rating: 8 out of 10.
VolumeUsable length: 90 cm. Ideal for securing frame and wheel to a fixed object.
LightweightWeight: 2.3 kg.
Warranty2 Years
Technical Informations

Unlike what many people may think, tamper-proof locks do not exist. A bike lock is there to make stealing the bike more complicated, to delay the thief and therefore act as a deterrent. A good lock has an anti-picking lock mechanism and is made out of materials requiring the use of specific tools, making theft more difficult.
Security rating
The security rating helps you choose the lock that is most suited to your use. In order to do that, B'Twin has defined a test protocol with an independent laboratory, the CNPP, based on real-life theft techniques. This unique protocol allows each lock to be given a comparable rating indicating how resistant it is to theft. This rating ranges from 0 (least secure) to 10 (most secure).
Lock body
Links made of hardened steel (65 HRC), one of the highest strength levels available for bike locks. Guaranteed resistance to hacksaws and hammers. Covered in fabric to keep it from scratching the bike frame.
Reinforced lock mechanism. Hundreds of different keys to limit the risk of theft. Comes with 2 numbered keys.
Information / Concept / Technology
Structure : 100.0% Acrylonitrile butadiene styrene (ABS)


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doesn't work every time.
Used for More than 1 year
Since i bought it it was not good. The lock stuck must oftime and i have to keep wiggle it to make it work. last week the lock doesn't want to open. luckily i couldn't lock my bike so the bike stayed in the bike shelter but now i am unable to unlock and bring it for refund. lost the lock and no refund:)
Nice lock, can I get additonal keys?
Used for 3 to 6 months

I have used the lock for a few months now, works great.

I've lost one of the keys so I now have only 1 left. Is it possible to get a replacement set of keys to match the lock? I'm worried about losing this one and not being able to get the lock off. Bike locks typically come with 3 keys,

It says in the description that the keys are numbered but htis doesn't appear to be the case, can you confirm this please?

Bike locked forever
Used for 1 week or less
Impossible to unlock my bike... must be an indoor lock as it rusted really quickly. Bike being chained for weeks now. Tryied all sorts of oil impossible to open it.... if anyone at decathlon reads this and has a solutioon i d appreciate.
Response of the brand
Dear sir,
I can confirm that this is a lock designed for outdoor use. I have used the very same one personally for nearly three years outside. Every few months I apply some spray grease in the lock (not WD40 etc...) but one of the most common causes of locks jamming up is grit and grime. Keeping the lock mechanism off the ground for as long as possible is a good tip.
Realistically in your case, the only way will be to saw or cut through the chain with a very large bolt cuter or axle grinding machine as this lock is very strong.
Peter Lazarus, National Cycling Manager, DECATHLON
Not enough to stop theft
Used for More than 1 year
I had great faith in this lock, but have just had my bike stolen with this securing it. It appears a bolt cutter can cut through the metal links.
Response of the brand
I'm very sorry to read that a thief stole your bike. It is terrible that this has happened and from my unfortunate personal experience, I empathise completely. This strong chain lock deters many would be thieves, particularly ones of the opportunistic variety. However it is also true to say that some professional thieves carry large bolt cutters and other equipment and given enough time can break through most bike locks. The hardened steel on the links is graded at 65 HRC meaning it is very strong indeed which would have slowed down the thieves considerably.
Peter Lazarus, National Cycling Manager, DECATHLON
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