I have a special road bike for Central London if I think I may need to park it somewhere. It's green with a slightly peeling finish and has quite a lot of rust showing. There's no fancy speedos or telemetry. The lights are big duracell blocks that unclip with a key. It has a plastic bag over the saddle and both a boingy spiral cable lock and a Kryptonite D-Lock. The saddle is a QR, but I hide the flip switch inside the plastic bag.
The reason is the expected life of an unattended bicycle in Central London is very short. This is a great shame, because London is trying to improve the cycle ways and to encourage cyclists on a series of alternateive and lightly used routes. I think its a great idea and this Sunday's Freewheel Day in Central London attracted tens of thousands of cyclists to zip around some of the best bits of central London which were liberated from other traffic for the day. Parliament, the Mall, Whitehall, Buck House were all included.
It may not be a practical solution yet, but if safe parking security and alternative routes can be provided then it becomes an attractive and interesting way to get around the mainly short distances of the central area.
Thanks, London and Hovis for facilitating this freewheel. Hmm, with Flora sponsoring the London Marathon and Hovis the Freewheel bicycle event, London sure knows which way its bread is buttered (!)