Sadiq Khan has unveiled plans for a second Superloop network of express bus services as part of his re-election bid.If granted a third term at City Hall, the capital’s Labour mayor is proposing to double the number of Superloop services from 10 to 20.The new collection of routes, dubbed ‘Superloop 2’, will include the recently announced ‘Bakerloop’ service, designed to provide an alternative to the unfunded £10bn Bakerloo line Tube extension.