One woman on the bus stood up for the young men and called out "welcome to New Zealand" to them before telling the man to behave himself.
The man then repeatedly told the woman to "shut your mouth up b****".
The woman who filmed the episode and who only wanted to be known as Noor, said she was terrified that the man would turn around.
"I think if he saw me filming him he would have come and punched me in the face."
Noor said she was wearing a hijab and would have been easily recognisable as Muslim.
The footage caught just a small amount of the rant, she said.
The two who were being abused refused to respond to the man.
The woman who stood up to the man was a "hero", Noor said.
"Everyone else was just looking at him, she was the only one who told him to back off.
"I think everyone was pretty scared of him as well."
She believed the bus driver was within his rights to kick the man off the bus.
An NZ Bus spokeswoman Tonia Haskell said the company was investigating the incident.
Advice to drivers in that sort of situation was to not confront aggressive passengers, "because that then puts them in a potentially dangerous situation".
The company's advice was for drivers to contact police and let them deal with the person.
