Roared on by a capacity crowd at Lee Valley VeloPark in London, Wiggins became the sixth rider to claim a Tour de France title and the hour record.
"I'm just glad it's done," he said. "It was torturous."
Wiggins, who becomes the fifth person in the past nine months to break the record, joked: "That's the closest I have ever come to what it's like to have a baby."
Wiggins, a multiple Olympic and world champion on track and road, surpassed Dowsett's record of 212 laps, set in Manchester, with 1min 42secs to spare and eventually completed 218 laps.
But the 2012 Tour de France winner fell short of the target he had set himself of 55.250km, or 221 laps.
