Cadbury has fired the starting gun for the next stage of its Spots v Stripes Olympic activity with the launch of a new chocolate bar, a link-up with Guinness World Records and a £6.5m marketing campaign.

A limited-edition chocolate wafer called Big Race Bar (rsp: 54p) hits shelves this month. With a crispy wafer base and cocoa creme and biscuit-piece topping, Big Race was "completely different" to any other bar on the market, claimed Cadbury.

The bar will replace Challenge bar, which has sold 14 million units since the launch of the first phase of Cadbury's £50m Spots v Stripes programme last August.

Its launch comes ahead of the 12-week Race Season campaign, which kicks off next month in place of the Challenge campaign.

Television, outdoor advertising and digital activity will direct consumers to the Spots vs Stripes website where they will be invited to take part in nine "everyday" races, including one to find out who can throw the most tea bags into a cup in the fastest time.

Cadbury has worked with Guinness World Records to develop the nine ideas, and consumers who clock up the best results will be recognised in the next World Record book.

"This next phase of the activity will focus more on the drama and humour of getting involved with Spots v Stripes," said Norman Brodie, general manager of the Cadbury London 2012 programme.

"We are one of the few Olympic sponsors to run activity so early and it is having a halo effect on all Cadbury sales even the ones that don't get advertised on TV."

Later this year, advertising for Cadbury's key brands will feature a "competitive Spots v Stripes twist", added Brodie.

"We want to focus on the personality of the individual brands by having a Wispa bar battling against a Creme Egg, for example," he said.

"We believe that each brand has a different personality and we will use this concept more in advertising this year compared with previous years."