Johnson disputes recession claim
He was speaking at an event in Victoria Park after Transport for London (TfL) scrapped a recorded message of the mayor warning passengers of "huge pressure on the transport network" amid claims the city has become a ghost town.
The mayor insisted businesses which had engaged with the Games were prospering.
Mr Johnson added: "What's happening is people are having a great time and those who are looking to engage with the Games are doing great business."
Asked what his message to struggling businesses would be, he added: "The message is, London is the place to be and I hope as many people as possible get involved with everything that's on offer from attractions at Stratford to those in central London."
Mr Johnson tried out a 45-metre high, 320-metre long zip wire at the London Live event in Victoria Park, where the Games are being shown on big screens.
But he was left hanging for several minutes as the wire lost momentum and got stuck over a crowd of people. As onlookers snapped photos on their mobile phones, he joked: "This is great fun but it needs to go faster."
The decision to scrap the mayor's message, which was played at stations across London, came after businesses said warnings to keep away from the city during the Olympic Games had worked "too well".
TfL insisted it had never advised people to stay away from London and added it had always planned to discontinue the recorded message at some point during the Olympics.
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