Three people have been charged with various offenses during Friday night's protest, while the rest were released pending further questioning, Scotland Yard said.
Police—who had earlier mistakenly said they had charged four people—confirmed that a 35-year-old Portuguese man, a 34-year-old Italian man and a 51-year-old man from east London will appear in court accused of public order offenses.
Scotland Yard said it knew a monthly protest by cyclists was planned for Friday but ordered the protesters to remain south of the River Thames to keep them from blocking more than 80,000 ticket-holders from the Olympics' opening ceremony.
Police said around 400 to 500 people attempted to cross the Thames to the Stratford area, where the Olympic Park is located, defying police warnings and attempts to stop them. The cyclists then split into small groups and some managed to reach Stratford.
Scotland Yard said it respected that people had a right to protest, but said officers must stop protesters who affect Olympic athletes, spectators and ordinary Londoners. It said officers began arresting the cyclists only after they ignored verbal warnings to leave.
The anti-capitalist group Occupy London, part of a global movement protesting financial institutions and capitalist policies, said some of the cyclists were members. They said police cordoned off more than 100 cyclists at one junction near the stadium as Friday's ceremony was beginning and held them there for several hours.