"I've run 2hr 48min in the past, but at 47 I am not getting any faster so I thought I would give people a laugh," he said.
His costume, which weighed 16lb, was built out of wood and nylon gauze, and included a stereo sound system which played a recording of bells chiming.
The tape machine batteries ran down before Aylmer's body clock tired. Aylmer, who got the idea from watching a TV programme about the Rio Carnival, had to stop at half-way to puncture some holes into his costume to act as an air vent as temperatures climbed towards the 70s.
"I'd been worried last month about it being windy but I hadn't expected it to be so hot," he said as he shuffled away with the typical gait of a foot-sore marathon runner, time having caught up with him after four hours and 26 minutes of running.
Another man sat against one of the equipment buses with his shoes and socks off. Both feet were bloodied. "I didn't feel a thing during the race," he said of his injury as four people carried him to the medical tent on a stretcher.
Lowestoft's David Read was disappointed with his time of 3hr 18min but was pleased to hear his friend, Paul Evans, had finished fifth, the first Briton. Like all the competitors, he praised the huge crowds who lined the 26.2-mile course. "They gave us all plenty of encouragement and support," he said.
Colin Gostelow, a race official and a regular competitor in the race, described the atmosphere at the Reunion Area in Horseguards Parade, where a giant diamond vision screen was replaying the race, as the "best ever".
A past winner back in the pack was Hugh Jones, the 1982 champion. He ran round with a mobile telephone filing regular reports for the TV channel, Eurosport. "The crowd were making so much noise I could not hear myself speak," he said.
When the race was over, and the hordes of spectators who watched Dionicio Ceron take first place had returned home, and after the many aching feet of the finishers crossed the final stretch of blue line, planning was already underway for next year's event.
But what the crowds - and even the runners - may not have realised was the complexity of the planning, the painstaking work of the many people who, for months before, devoted endless hours figuring the logistics of getting 26,000 runners from Blackheath to the Mall in a city where myriad cars, buses and taxis wage daily battle for space on the roads.Reuse content