Transport for London (TfL) is unlikely to provide locks with its hire bikes when the scheme is launched in 2010.
The move is intended to retain a high turnover of users getting from A to B sustainably, not, it seems, from A to B to C.
But what if you just want to pop into a shop for a bottle of water or a newspaper, one blogger plaintively appeals. The answer is simple, says TfL, bring your own!
"If you do want to use your own lock you can," said a TfL spokesman. "If it's locked securely to a cycle stand or similar, fine, the point is why would you do that if the docking station is just around the corner?"
TfL says users of the 6,000 bikes will never be more than two minutes away from one of the 10,000 docking stations, the message being, dock up, don't lock up. The Parisian Velib scheme, which the London one is loosely modelled on, does provide locks, but TfL says they're no good.
"The Paris scheme has a lock attached but it would probably register about "Z" on the safety scale," says the spokesman. "They wouldn't offer much resistance to a thief, however it's nonsense to say that we've "banned locks"!
"The aim is to achieve a very high turnover to keep as many people using [the bikes]as possible, therefore we don't want people to keep hold of them. There will be a docking station every 300 metres."
The pricing model is also a disincentive to those thinking about using the bikes to run errands, or meet friends for lunch.
The spokesman says: "It's a bit like sitting in a cafe while the taxi's outside with the meter running."