The motorcycle, a tractor-trailer, and a Honda Pilot were involved in a wreck near Exit 58 around 11:45 a.m., according to state police.
The Lehigh County Coroner's Office said the motorcyclist was pronounced dead at the scene. Authorities said he was a Coppersburg resident but did not report his name Wednesday.
The 59-year-old tractor-trailer driver and the 42-year-old in the Honda were not injured, troopers added.
I-78 was closed until about 3:30 p.m. while crews worked the scene.
State police and the District Attorney's Office are investigating, according to Coroner Daniel A. Buglio.
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