Matthew Goicochea, 31, was riding northbound just before 4 a.m. near 25th Street when he "failed to navigate the roadway" and fell off the vehicle, police said.
As Goicochea lay on the roadway, he was struck by an unknown vehicle that did not remain on the scene, police said.
He suffered severe injuries and was pronounced dead at the scene, police said.
Goicochea has been with the department since 2022 and last year received the Thomas Wylie Medal for rescuing an unconscious victim from a fire in the Bronx.
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