Neil Poundford was locked up in August last year for sexual assaults on a 17-year-old girl on a bus and a 13-year-old as she waited at a bus stop.
Poundford was also made the subject of a sexual harm prevention order prohibiting him from using public transport unaccompanied for a period of ten years.
Leeds Crown Court heard the 59-year-old was released from prison on licence in April this year.
Peter Yates, prosecuting, said police officers from the public protection unit went to Poundford's home in Wakefield to pay a "routine visit" and spotted him walking down the street.
The officers followed Poundford and saw him board a bus on Horbury Road.
They followed the bus until Poundford got off the vehcile in Wakefield city centre.
Mr Yates said Poundford was arrested and told officers: "Yes I did it. I have been stupid."
The prosecutor added: "He said he was aware of the order but that he just wanted to get on a bus and act like a normal person."
Poundford was released on bail but officers observed him catching another bus on May 15.
He was arrested again two days later and told police: "Yes, I thought it was you who saw me when I got on the bus."
Poundford, of Horbury Road, Wakefield, pleaded guilty to two breaches of a sexual harm prevention order.
Emma Downing, prosecuting, said Poundford had sat deliberately away from people during the journey and no members of the public had been placed at risk.
Miss Downing said Poundford had used public transport as he is too old to walk into the city centre.
The barrister said Poundford had been placed in accommodation out of the city centre but liked to go there to visit the library and see friends.
Poundford was given another jail sentence of 16 months.
At his sentencing hearing last year, the court heard Poundford targeted the 17-year-old victim as she was travelling on the bus between Wakefield and Dewsbury.
He sat next to her and began talking to her before grabbing her face and saying: “I think I recognise you.”
Poundford then started to talk about driving lessons and touched the victim on her arm.
The victim felt frightened and got up to leave then Poundford slapped her behind as she walked away.
Police obtained CCTV footage from the bus and were able to identify Poundford.
He was arrested and released on bail but targeted a 13-year-old girl at a bus stop in Horbury.
Poundford approached the girl on Westfield Lane and made a comment about her jeans before touching her knee.
Poundford then showed her a bank book and said he had Â£3,000 in his account.
He also touched her face before she walked away and told a friend what had happened.