I wrote here a while ago that the Englishman Alan Bate had gone around the world by bicycle in 106 days, an astounding feat. I have since learned that he did it with a support crew. While still an astounding feat, having your luggage carried for you in a support wagon, having your meals prepared for you, being able to sleep in the back of a minivan without finding shelter nor preparing a tent, is not much like real bicycle touring. Presumably the car would take you over the steepest, slowest sections of road or even across whole mountain ranges, so the whole trip could be done on level ground.
The real record-holder by most reckonings is Vince Cox who went around the world, covering a minimum of 18,000 miles by bike, in 163 days. He traveled alone, carried his luggage with him on the bike, and slept where he could. Ironically Cox' 2010 record was broken only four days after it was set, by Bate.
Cox' record meant riding at least an average of 110 miles per day for five and half months on a fully-loaded tourer. That is a feat of almost magical determination and fitness.
On February 19th a dozen riders set out, nine from Greenwhich, England, one from Bangkok, another from New Zealand, and still another from the Isle of Man. The date was set for 160 days before the opening of the London Summer Olympics, on the theory that the winner will arrive in London during the event.