LONDON (Reuters) - Bookmakers expect record gambling on the 2012 Olympics after the opening ceremony prompted a flood of bets on event mastermind Danny Boyle receiving a knighthood - and confusion over wagers laid on who would light the Olympic flame.

Since London won the Olympics in 2005 gamblers have forked out on the closely guarded secret of who would light the flame, with British five-times gold medalist, rower Steve Redgrave, the clear favorite.

But in the end, seven young athletes selected by seven British Olympians lit the flame in unison, causing divides in the bookmaking ranks over how to handle the bet.

Ladbrokes and Stan James decided to pay out on all seven of the British Olympians involved which included Redgrave, Daley Thompson and Kelly Holmes.

William Hill voided all bets and refunded about 50,000 pounds ($80,000) wagered on the event since 2005.

"It is a bit disappointing as we've been taking bets on this for years and in the end there is no winner. There is no way anyone could have predicted any one or all of the seven people chosen," William Hill spokesman Graham Sharpe said.

Stan James said it had voided all losing bets, meaning punters got their money refunded.

"It's a once in a lifetime occasion and we thought it appropriate to make this gesture after such an incredible start to the London Olympics," spokesman Rory Jiwani said.

Bookmakers said the success of the opening ceremony devised by Boyle, who won an Oscar for his movie "Slumdog Millionaire", had ignited a feelgood factor and already boosted gambling interest in the Olympics - and not just in the sports.

QUEEN ON FILM

Boyle, 55, is being tipped to be awarded a knighthood in the New Year Honours List by Queen Elizabeth, whom he somehow managed to persuade to take part in her first movie role.

During the opening ceremony, a film showed James Bond actor Daniel Craig arriving at Buckingham Palace and escorting the Queen to a helicopter. Minutes later a helicopter appeared over the stadium and released two parachutists. The Queen then walked into the stadium to huge cheers from the 60,000 crowd.

"Everyone was amazed and wowed at what Boyle did last night," Ladbroke's spokeswoman Jessica Bridge said. "Before this Danny Boyle was 2-1 to get a knighthood but due to the sheer volume of bets we have cut this to 5-4."

She said the largest bet so far was 5,000 pounds.

Coral spokesman David Stevens said they were running odds on Saturday of 6-4 that Boyle is knighted next year, having been 4-1 immediately after the opening ceremony.

Jirwani said the ceremony had boosted patriotic pride with odds of 4-5 that the British team will win more than 22 gold medals compared to 19 in Beijing which could push them above Russia to be third in medal table behind the United States and China.

Bookmakers are forecasting between 50-100 million pounds ($80-160 million) will be wagered on the London Games, which would be four to five times more than gambled at Beijing but still way short of other major sporting events.

They expected plenty of money on football and tennis with some interest in cycling after Bradley Wiggins' Tour de France victory.

The men's 100 meters race, a highlight of the Olympics, was not seen as a great draw for gamblers.

Mark Maydon, commercial director of the Sporting Index Group, said the odds were against Jamaica's Usain Bolt setting a new world record at this event after stunning the world with his 9.69 second win at Beijing. Bolt cut this to 9.58 a year later.

He predicted the 100 meters would be run in 9.71 seconds with only half of the 8-strong field running under 10 seconds.

Sharpe said gamblers were not enthusiastic about the race.

"It really is a two-horse race between Bolt and (fellow Jamaican) Yohan Blake and gamblers like to have a bit more competition than that," he said.