CYCLIST Stephen Green aimed to raise £1200 in a charity cycle ride at the weekend.

The 55-year-old collapsed and died on the Olympic road race circuit and within hours the total cash raised for a children's degenerative disease charity has increased by thousands.

As of Wednesday morning the total with gift aid was more than £18,000, with donations expected to rise further.

Mr Green, from Green Road, east Reading, had started to climb the 294m Leith Hill in Surrey, one of the hardest sections of the route, when he collapsed.

He received immediate medical attention from paramedics and an air ambulance, but the death was confirmed at the scene.

Mr Green had been raising money for the charity Action for A-T (Ataxia-Telangiectasia).

Andre Hutchinson, who donated £10 to Stephen's cause said: "As a fellow cyclist on the Prudential 100 my heart goes out to your loved ones. May this legacy for the charity be a fitting tribute to your compassion. RIP."

Danny Margerum, who also donated £10 added: "I was just behind on Leith Hill and hoped it wouldn't come to this. Thoughts with family and friends. RIP."

Sean Kelly, spokesman for the two-year old charity said the money would be their single biggest donation from an individual in their short history.

He said: "It's terribly tragic what has happened, especially as he was trying to do something to improve the lives of others. 

"All of us here at the charity express our condolences to his family and friends. It's been overwhelming and we are extremely grateful firstly to his family and to the fellow riders who have made donations and left moving comments."

The founder and client director of branding and marketing company Greenfisher, based in London Road, was well known throughout Berkshire as a local football referee for the Thames Valley League, formerly the Reading League, which plays on Saturdays.

He had been chairman of the Reading Referees Association in the past and chairman of a local cup competition. He had also worked as a referee tutor.

Friend and fellow referee of 30 years Dick Sawdon Smith, 83, said Mr Green would be greatly missed.

He said: "Stephen was a very nice and hard working man.

"Stephen was a senior training officer for Reading referees. He is known to many referees who would have started their careers under his tuition.

"Through his contacts he bought many of the top refereeing speakers to Reading, including premier league referees like Howard Webb.

A RideLondon spokesman added: "At the request of his family, we confirm that Stephen Green, aged 55, from Reading was the rider who collapsed on the lower part of the ascent of Leith Hill during the Prudential RideLondon-Surrey 100 on Sunday 2 August.

"All involved in the organisation of the event express sincere condolences to Stephen’s family and friends."

An inquest will be opened and adjourned later this week so that a coroner can establish the cause of death.

Mr Green's charity page can be found at: http://uk.virginmoneygiving.com/fundraiser-web/fundraiser/showFundraiserProfilePage.action?userUrl=StepGreen&d-49489-p=4