Speaking at the SportAccord convention in Laussane Bach was emphatic in his conviction everything would come together.
"We know the current economic and political situation in Brazil will continue to make the final preparations challenging," he admitted.
"I remain convinced that the Olympic Games Rio 2016 will be truly spectacular," he said, offering two reasons for his position.
"The Olympic Games enjoy the strong public support of the Brazilian people. Secondly, the organisers can count on the solidarity of the Olympic family and the sporting world."
Also Read
"With regards to protecting the clean athletes, the IOC has strengthened the world's anti-doping system and made the sanctioning of doped athletes independent from sports organisations," he said.
"The Court of Arbitration for Sport (CAS) will handle cases from the Olympic Games Rio 2016 onwards. We are convinced that all these changes are necessary to better protect the clean athletes and enhance the integrity of sport."
Brazil's president Dilma Rousseff insisted on Tuesday preparations for the Games in Rio are ahead of schedule.
"We have transformed Rio: I hope this will be a great Games for Brazilians and for everyone else."