[nkangoh]

This is slightly off topic, but why aren't folding bikes or scooters more popular? Their folding mechanism allows you to take them with you which would presumably prevent theft more than a lock. If a bike lock is the only thing that's keeping your bike from being stolen it doesn't seem like it'll work more than it just delays the inevitable.

Plus aren't locks really inconvenient to carry around with you? 10+ pounds is a lot when your bike is only 20lbs.

[lambda]

I ride a Brompton, and that is one of the big reasons; I can just take it inside, and stash it under my desk, rather than having to lock it up outside.

However, it is inconvenient in some situations. When I go to a bar, or restaurant, or movie theater, it's sometimes hard to find a place to put it that's out of the way. Since a lock is cumbersome and inconvenient, and I don't usually need it, that means I don't make a habit of carrying one, but then I'll hit a situation where it really would be more convenient to lock it up than take it in, but now I don't have that option.

That said, I do ride my Brompton as my daily commuter, and do bring it in with me, and most bars, restaurants, or the like do have enough room for me to stash it somewhere. But you do have to be willing to put up with people who think it's a little strange, or the people who joke "hey, I don't try to bring my car into the bar", and you do sometimes need to be creative to find a way to stash it securely and also out of people's way.

[nether]

I say this as a proud Brompton owner, but to most people they're just weird. They're also a bit more expensive, you get less bike for a given amount. They're not that light. I often lock mine up outside because I don't want to a haul a 26 lb block up a flight of stairs.

No lock weighs 10 lb (you can read the article), and 20 lb is a pretty light bike. 3 lb lock for a 25 lb bike is more realistic (my roommate's 56 cm aluminum road bike is 26 lb).

[twic]

Even 3 lb vs 25 lb is the wrong comparison. Why does the weight of the bike matters? What matters is the total weight the rider has to move - which is something like 25 lb for the bike, 20 lb for a bag, and 200 lb for the rider themself. 3 lb is peanuts on that.

[DanBC]

There are a lot of not-very-good-bikes -- usually refered to as "bike shaped objects". These cheap bikes make the good folding bikes seem expensive. (Is this like an "overton window"?)

A good folding bike is probably a great choice for many people.

[Someone]

A good folding bike, at best, is a decent bike. Folding bikes have smaller wheel diameters, lower frame stiffness, and larger relative weight.

[notatoad]

and carrying your folded bike around with you when you aren't riding it is far less convenient than carrying a lock while you're riding the bike.

[Doctor_Fegg]

The only bike with a no-compromise fold is a Brompton. Bromptons can be stashed by your desk and are ideal for city riding, which is why they're such a common sight in London, Oxford and other UK cities.

But for other types of cycling they don't cut the mustard. I have a Bike Friday and my wife has an Airnimal, both of which are exemplary folders - the BF goes anywhere and the Airnimal goes road-bike fast. But neither of them has anything like the compact fold of a Brompton.