NEW YORK — NYPD officers assigned to subway lines are now conducting solo patrols to expand law enforcement’s presence on mass transit, Mayor Eric Adams announced Tuesday, over the objections from the city’s largest police union. The solo patrols began on Monday night, Adams said during an afternoon press conference in Brooklyn, where the NYPD is demolishing 100 dirt bikes seized during a crack down on reckless motorbike riders. “For many years we had a version of what was called single patrol. I did it as a police officer,” said Adams, a former transit cop. “I wouldn’t have anyone do a job th…