I've got several YourPlus Abus locks (all keyed the same) so that I can have one key for basically all the family bikes. The other day I noticed that one of my D-Locks had a plastic part missing, namely where the Abus logo is usually placed. Behind where the logo once was you see the solid metal of the meat of the lock. There is a 7 digit number there.
As it's trivially easy to get a fifty dollar lock keyed to the same yourplus code as mine (if you know my code) and then steal my bike, I'm hoping someone can help me sleep better at night by telling me that it's in no way related to the bitting values of the lock.
Lock in question is the Granit 640.

Yes, I've contacted the manufacturer asking the same question but haven't heard back yet.

  • 2
    Did your locks came with an Abus key card (I had it for some of my Abus locks)? Or any other sort of documentation for the locks stating the numeric code? If so, compare the code on the card with the code on the lock body. I doubt they would match, but if they do that would be a major security flaw. And please post the manufacturer's answer once you get it. Oct 20, 2019 at 14:52
  • I'm almost certain most thieves would just cut through it with an angle grinder, they won't waste valuable seconds looking for lock codes. Why would anyone for that matter when a decent angle grinder is just as good. Unless the thief is security conscious and wants to lock up his newly nicked bike.
    – Dan K
    Oct 21, 2019 at 4:21
  • 1
    @DanK If there are multiple bikes with the same lock and said this is trying to be discreet, it would be an excellent idea to use an original key imo. If you have a key, you make much less of an impression on people. Actually you don’t even register on people’s minds. With an angle grinder, you’re “that person with the angle grinder” and if you’re trying to get away with 5000$+ worth of equipment, it’s a no brainier if possible. Oct 21, 2019 at 8:22
  • Often the code printed on a lock isn't the bitting code itself, but can be converted to it using a more-or-less secret lookup table or formula.
    – Chris H
    Oct 21, 2019 at 8:34
  • @ChrisH A Kryptonite lock that I have has its number printed on its keys (can be used to restore keys, confirmed by reading the manufacturer's documentation). An Abus lock I also have came with a separate card with a number on it, nothing printed on keys. I like Abus's approach more, as it gives a tiny bit more security (harder to compromise the code). On the other hand, a separate card is easier to misplace. I also think that there should be no need to print anything key-related on a lock body, as it is a lock core that should match the key, and it is manufactured separately. Oct 21, 2019 at 8:56

1 Answer 1


As per question, I had e-mailed the manufacturer (Abus) regarding the meaning of the number. Apparently it is the serial number of the item (bike lock) itself. Also Per e-mail from the manufacturer,

"Due to security reasons it is not possible to order spare keys with this number".

On each YourPlus key card is the YourPlus code for your key/lock as well as the lock's serial number. I'm not sure if Abus partners would be able to request a new key for serial number x (perhaps a thief working at a key shop) or look up yourplus codes for specific serial numbered locks, though I highly doubt the latter.

  • Thank you for following this through with the manufacturer! From a truly paranoid perspective, having lock bodies and matching keys identifiable at any point in time outside of your control can still be used to compromise locks somewhere in the supply chain. Even if one number cannot be deduced from another, a middleman, with access to both numbers at the same time, can start maintaining a number-number correspondence database, which can be used for restoring keys. The only protection I see against such attach is either to destroy lock's identity (mange its serial number) or to swap the core. Oct 24, 2019 at 13:57
  • [to continue] A seller can always make a copy of the key before selling you a lock; but then he/she has to find that lock to open it with own key copy. Knowing where you live will definitely help to mount such an attack (so buying locks anonymously for cash should make you less traceable). Alternatively, you need a possibility to "reprogram" the lock's core so that any previously made key copies simply won't work on it. Oct 24, 2019 at 14:01
  • It's a 7-digit number, though, so to have a decent chance of having your lock in a database the middleman would need to have sold (and cataloged) millions of locks, unless it's the same middleman who sold your lock.
    – Charles
    Jun 15, 2022 at 20:02

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