It's never fun to leave your bike outside, but for some it is a necessity or part of the daily commute. There is always the risk of theft and if someone really wants your whole bike or a part of it, they will find a way. There are a variety of ways to deter thieves or slow them down and as a daily commuter I seek ways that are as practical as possible.
I do have a one of those hefty bike chains that could easily be used as a boat anchor. I ride with it around my waist and it is not hard to get used to riding with it. To lock up I loop the chain around the frame and my front wheel, but it is not long enough to include the rear wheel. Of course I could take off my front wheel and loop the lock through the rear wheel, front wheel, and frame, but doing that over and over just ain’t no fun.
Some people end up using a separate lock, chain, or cable for the rear wheel. When I first moved to NYC I noticed that many people used plumbing clamps to secure their front or rear wheel (the clamp loops around the quick release lever and one stem of the fork or rear lower tube). It's a great thought, but it would not make changing a flat very easy. I liked the idea though and came up with my own security hack.
I ended up using padlocks on my rear wheel quick release levers. The perfect fit is not necessary if you just buy a small bungee cord so the lock does not rattle around. When the weather gets nasty I wrap the locks with plastic wrap to keep the grime out.
You could of course go with a quick release skewer with a locking mechanism, but that would not have the city flair a protruding lock does. Just make sure you carry the key or remember the combo when that rear tire goes flat.

Good tip,something I've never given much thought to (and being new to city living/utility riding....),thanks :)
The DC
Posted by: Disabled Cyclist | 02/21/2012 at 07:42 AM
I really can't imagine the environment, or what it is like to live in an area where hacks like this are necessary.
I know they exist, but I'd like to pretend that they don't. During fair weather, I leave my entire fleet of bikes leaning on my garage, next to the garbage cans. Never, ever, ever do I have the fear of theft. <3
Posted by: WV Cycling | 02/25/2012 at 05:18 PM
This doesn't work on most mountain bikes. Those don't have holes where you can hook the lock trough. At least I've never seen one that does.
I'm riding a mountain bike for commuting, with disc brakes and screw out studded tires. My bike was stolen in December cause it was secured with a cable. I learned it the hard way that cables aren't secure. I was lucky, I found my bike the next day and the police got it back for me. I bought a chain just long enough to loop trough both wheels and the frame. I had a moment where I thought about getting a U-lock too, but I gave up the idea. Way too heavy. Though I might get one and leave it locked on my college's bike rack and just bring the chain around.
There's a point where it just gets paranoid. When I bought my bike, I filled all the Allen screws with hot melt glue. I took the habit of always taking my seat with me, so it doesn't get stolen and because it stands out too much in the bike rack. A motivated theft that really wants your bike will get it, no matter how secure you think it is.
When the police gave me my bike back, I took it inside and tuned it for winter. Home made screw-out studded tires and full size fender set on a suspension fork. There was some hacks to be done, if you're interested, let me know. I took a bunch of pictures before I took my bike out in the slush ;)
Posted by: Kim | 02/27/2012 at 01:26 AM