Banking giant Barclays has announced it will be the £25m sponsor of the Mayor of London's bicycle hire scheme.
The project, renamed Barclays Cycle Hire, will install 6,000 bikes at about 400 docking stations across zone one from 30 July.
The new deal will also introduce 12 new cycle "superhighways".
Two pilot cycle lanes, from Merton to the City and from Barking to Tower Gateway, launch on 19 July with the remaining promised for the end of 2015.
People will be able to access the bikes 24 hours a day from docking stations in nine boroughs and several Royal Parks in central London.
The mayor also announced 45 roadshows across the the capital to show Londoners how to register and pay for the system.
Fifty of the Barclays-branded bicycles were also delivered to the nine boroughs that the scheme will operate in, following the announcement.
Local residents from those boroughs can sign up for advanced cycle training and be the first to ride the bicycles once the scheme goes live.
Mr Johnson said: "Barclays are going to help us deliver the cleanest, greenest and healthiest form of public transport that London has ever seen."