The court heard how the sentence was academic though, as there was a deportation order in force against Kadam.
The incidents took place on two consecutive days on inter-city buses in Auckland and Northland.
On August 28 last year - weeks after he had arrived in the country - Kadam boarded a relatively quiet bus at Kawakawa and immediately sat near the 17-year-old victim, who was travelling alone.
He tried to talk to her but she could not understand him through his "heavy accent", Judge Sinclair said.
Eventually, he sat next to the girl, forcing his shoulder and leg against hers.
When the girl asked him to move so she could get off in Whangarei, he remained seated and stood up as she tried to squeeze past him.
"She felt a hand [up her skirt] on her upper thigh and quickly moved away from him," the judge said.
She sought refuge in some nearby public toilets and remained there for a considerable amount of time after she saw Kadam follow her off the bus.
The next day, Kadam was on another bus when two teenage girls boarded at Takapuna.
The 16-year-old victim and her friend noticed him staring at them and thought he seemed "creepy".
When he got off the bus at Kawakawa he reached over and grabbed the right breast of the girl.
His lawyer Phil Hamlin said, despite the previous guilty pleas, his client wanted to defend the charges and his defence was that the molesting was "accidental".
"I'm not persuaded he has an arguable defence that warrants vacating these pleas," Judge Sinclair said.
She did not accept Kadam's explanation, which she said had been contradicted in interviews with probation during which he exhibited concerning attitudes towards women.
"This offending was worrisome," the judge said. "Those young women were entitled to feel safe on public transport and you trampled on their rights. They were vulnerable and defenceless."
But Judge Sinclair forbid photographs being taken of the defendant after Mr Hamlin cited Waikato District Health Board documents.
Immigration New Zealand confirmed the 31-year-old would be deported to his partner of five years and four-year-old daughter later this month.