Promise it's decent - I cropped out the guy proudly displaying all just behind these two. There were other options, but these guys do look as they are enjoying themselves.
@steeler In the UK cyclist helmets are recommended not legally required. Cyclists are required to have a reflector and bell, and lights if riding at night, but cycle helmets are optional. The bag on the Santander (was Barclays) bike is reassuring - he might have some clothes on him.
@pixiemac sure - the other picture I put up on Flickr was used by the Londonist for their article, along with others. (I have some full frontal pictures I haven't put up anywhere)