Shimming D-/U-Locks

[MrTornado]

Hey guys, this is my first Topic so be gentle. I, like most of the cyling community, loathe bike theves. I attend university in a city where bicycle theft is the biggest crime committed.

In order to protect myself against bicycle theft I use a D-/U-lock ( I think D- is what they're called in the UK and U- is for the US.) I've just been playing around with my lock and I'm fairly confident it can be shimmed. I've had a go with the part of a drinks can but the metal's too thin because the spring is very strong. I'm sure it could be done with a custom made thicker shim because there's a large enough gap for sure.

My questions are:

1) Is this a known attack?
2) Is it common?
3) How much do I have to pay to get a lock that anyone couldn't open in a minute?

[GWiens2001]

Not aware of any bicycle locks in the D/U format that can be shimmed. Picked, yes. Bypassed? Can not discuss bypass on the public forum. However, don't think picking is too common a theft method. Personally would avoid tubular locks or cheap disc detainer locks. Your biggest threat is going to be somebody cutting the lock/chain/cable.

Gordon

[MrTornado]

If you use just a D-/U-lock you're pretty well guarded against someone cutting through it. Most of them are resistant against bolt cutters and hacksaws. Of course someone could take an [redacted] to the [redacted] but no one is going to want to be using an [redacted] in a public place. It's hardly discrete.

I thought you could discuss bypassing so long as it's not bypassing advanced locks? I found this list of things not to talk about: "bypass of high security locks, safe lock manipulation, advanced pick tools, automotive bypass & picking discussion and destructive entry. "

Is there a more up-to-date list somewhere?

[Squelchtone]

If you use just a D-/U-lock you're pretty well guarded against someone cutting through it. Most of them are resistant against bolt cutters and hacksaws. Of course someone could take an [redacted] to the [redacted] but no one is going to want to be using an [redacted] in a public place. It's hardly discrete.

I thought you could discuss bypassing so long as it's not bypassing advanced locks? I found this list of things not to talk about: "bypass of high security locks, safe lock manipulation, advanced pick tools, automotive bypass & picking discussion and destructive entry. "

Is there a more up-to-date list somewhere?

You're right, the rules are old and vague and need to be reassessed. No bypass is to be discussed currently on any level. It teaches the bored and the lazy easy ways to steal, and we don't want this forum to enable that. We'll let youtube do a fine job of that with their plethora of bypass videos as made by mischievous teenage boys.

Squelchtone

[MrTornado]

Thanks for the clarification Squelchtone. Please forgive my mistake.

Edit:

If I may be so bold I think it would be helpful for newcomers, such as myself, to add a definition of what classes as a High Security lock. The advanced forum says it's for: "Discussion on lock picking and smithing for high security locks such as Abloy, Medeco, Primus, Miwa, Sargent, Dom, Mul-T-Lock to name a few."

However, to me at least, it doesn't seem to make sense to define high security locks by the brand name. Disc detainer locks seem to fall under the umbrella of high security locks yet they are not necessarily made by Assa Abloy or its subsidaries. Some are available off eBay very cheaply. Furthermore many locks made by big brands in high security are no longer fit to be considered high security. It would seem more appropriate to define high security locks by features (magnetic components, side bars, rotationally sensitive pins, disc detainer style etc).

I do not mean to speak out of place however I feel clarifying the rules would greatly help newcomers decide what is and isn't appropriate. I understand that coming from a new member this may be misinterpreted. I mean no disrespect to the wonderful community the administrators/moderators have helped to build.

[Squelchtone]

No worries, but you yourself have stumbled upon the very problem we have, what does it mean to be a high security lock? is it the brand? a model number? what it is used for? This is whats stopping us from just rewriting the rules quickly and publishing them, there's always that one lock or one application that makes us revisit the list and rethink how we categorize high security locks or "advanced" topics.

Enjoy the forum and dont worry too much, if you post something naughty, we'll be sure to put it in the correct area.

=)
Squelchtone

[spoonzor]

If you can't lock the lock without the key you probably can't shim it.
If you meant the "D/U locks" that i imagine you mean, you usually need the key to lock them/can't just click them to closed position without turning the key.

[MrTornado]

This specific model can be locked closed without the key.

[spoonzor]

Well there you have your answer. If you think about it, a lock that can be closed without the key can usually be opened without the key too.

My answers are:
1) Yes
2) Yes
3) Just forget about it unless you have a very expensive bike.

To clarify answer 3: Keep in mind that most thieves will use a small bolt cutter and have no knowledge about locks whatsoever.

There are a number of threads on this forum on "what is the best lock for my bike", please use the search if you are really interested.

[boogietoot]

Try park your bike next to some one with a similar price tag and worse locks.. other wise.. the abus 83/45 and 83/50 padlocks you can lock without a key and can't shim because of the double ballbearing locking mechanisims