The Mayor said that his investment in cycling would provide a boost to all Londoners, not just lycra-clad bike enthusiasts.
"The reason I am spending almost £1 billion on this is my belief that helping cycling will not just help cyclists. It will create better places for everyone. It means less traffic, more trees, more places to sit and eat a sandwich.
"It means more seats on the Tube, less competition for a parking place and fewer cars in front of yours at the lights. Above all, it will fulfil my aim of making London's air cleaner."
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Metropolitan Police officer, Tom Harrison, has been crawling the course since the race began on Sunday morning.