Here in the UK, savvy bicycle commuters buy an extremely heavy chain [1] and leave it locked up outside their office. Bicycle locks are a compromise because they need to be light enough to carry. If you don't carry your lock, you can use a massive lump of metal.

[1] https://www.youtube.com/watch?v=7lDcViM1EKc

Then UK thieves are clueless. The recommended padlocks (SS50C or SS65C) can be picked (search for model + "picked" on youtube) in less than 30 seconds. For bystanders picking the lock looks like you are just too stupid or drunk to use your key.

I would imagine that an angle grinder works equally well with all locks regardless of brand.

Cold spray and a hammer is faster and much less noisy and does not come with a free pyrotechnics display.

There's a video where a guy breaks a bicycle lock with a angle grinder, in the middle of the day in a city center. Nobody bats an eye. Breaking the lock doesn't have to subtle.

Does that work? And what do you mean by cold spray exactly? Ralgex?

If it wouldn't work I wouldn't write it.

https://www.youtube.com/results?search_query=cold+spray+bike...

Second to that. Metall becomes brittle at -20. Bing.

Because clearly, when stealing a bike, you want the entire neighborhood hear you for ten minutes, emitting sparks everywhere, while you had to bring an angle grinder.

You're supposed to be somewhat discreet when doing that, not warning everyone.

Most people's locks can be cut with a strong set of shears. The other ones are usually not worth spending your time on unless it's everything there is. In which case, like @jacquesm said, freezing temperatures are an excellent solution. More of a middle of the night thing though. Shears work 24/7.

I have 'stolen' my own bike after losing the key. It was in bright daylight in plain view with a ton of people walking by. No one said anything.

Yeah I think the main benefit of using two locks is that a thief will just go for an easier option. IIRC similar rules apply to home security. It's not only about deterrence; making your house more of a nuisance than other houses is important too.

I agree - you don't need to outrun the bear, you just need to outrun your friend.

It does, but it requires power and time, and makes a ton of noise. Most thieves prefer something quick and quiet.

welp, if this entire thread taught me anything, is that I need to lojack (or whatever it's called) my bike.