Mark Cavendish believes the Olympic road race will be ‘like a Classic’ having sampled the course with victory in the London-Surrey Cycle Classic.

Cavendish, fresh from becoming the first Brit to win the green jersey at the Tour de France, was part of a select group of 14 riders to contest the sprint in front of Buckingham Palace on The Mall.

The race was run over 140km of the route to be used during London 2012, tackling two laps of a Box Hill circuit, while the 250km Olympic race will contest nine.

And, despite a flat 50km run-in back to the capital, Cavendish reckons the extra distance, combined with seven additional circuits of the climb, a favourite with club cyclists in Surrey, will leave only a small group of riders to contest the gold medal.

“Today wasn’t about getting a feel for next year’s race,” said Cavendish, who proved his worth in the Continent’s one day races with victory in the 2009 Milan San-Remo. “Next year will be like a Classic. Groups will go, groups will come back and eventually a select group will get away that will include puncheurs, attackers and sprinters.

“We’ll all have to be on our best form for it – I’ll have to be on my best form – but I’m confident that I can prepare. It certainly won’t be a big bunch sprint but if I can be there with a solid group of team-mates then we’ll be able to make it a sprint.”

Cavendish has been widely tipped to win Great Britain’s first gold medal of 2012, with the road race set to take place less than 24 hours after the opening ceremony, but American sprinter Tyler Farrar, who claimed his first Tour de France stage victory in July, believes it’s impossible to pick a winner.

“I think the circuit is harder than most people are giving it credit for so nine laps of that circuit will be quite hard, especially for guys like me,” said Farrar, who saw his hopes dashed by a crash in the closing stages. “On the other hand, it’s still a long way to the finish from there so there’s still time to come back.

“It will be an unpredictable Olympics. I still think it will be a sprint but the size of the group might not be that big.”

Organisers claimed more than 100,000 spectators lined the 140km route to give Cavendish et al a taste of what to expect when the Games arrive in London next year.

“It was be pretty incredible and if it [London 2012] can emulate the crowds from the prologue of the 2007 Tour de France then it’s going to be spectacular,” added Cavendish. “The course at the start, finish and the whole way round was nice. I’m pretty excited about it and it just shows how many people are into cycling in Britain at the moment.”

Italy’s Sacha Modolo finished second in the sprint, while France’s Samuel Dumoulin claimed third. Rapha Condor Sharp’s Kristian House, national champion in 2009, won the King of the Mountain competition after spending much of the day in a four-man break.

“I found it a little dangerous at the start,” said Dumoulin. “The Olympic Games, with nine laps, will be difficult for the sprinters.”

House added: “Nine times up Box Hill will be a little harder for the sprinters but I don’t think it will effect it massively. It was quite a good climb. There were quite a few people on the side of the road supporting the riders.”