"I want to thank the organisers and the wonderful crowd who made all the difference as we cycled by, helping to spur me on to finish the gruelling 100 miles in a respectable eight hours.
"Huge congratulations to everyone who took part
"RideLondon is now firmly on the map as one of the greatest cycling events in the world."
Mr Johnson, who battled with a puncture to complete the challenge in just over eight hours, was taking part in one of a number of events this weekend in what was billed as the UK's largest festival of cycling.
Mr Johnson said: "This is a great day for cycling, and for this city.