In May the Independent Monitoring Board expressed concern about a lack of "meaningful activity" for some inmates.
Governor David Taylor said the scheme offered offenders both work and skills.
Each year Cambridgeshire Police recover hundreds of stolen or abandoned bicycles.
Those not reunited with their owners are offered for sale at auction.
Unwanted bicycles are sent to the young offenders' unit and once refurbished are donated to victims of crime and disadvantaged families who might otherwise be unable to transport their children to school.