State troopers said it happened around 12:45 a.m. on Route 22. A 2008 Suzuki motorcycle collided with a 2020 Toyota Camry in the westbound lanes near mile marker 319.6, authorities said.
He was taken to Lehigh Valley Hospital-Cedar Crest with "serious injuries," according to state police.
The driver and three passengers in the Camry were not hurt.
Route 22 traffic was detoured onto 15th Street while troopers investigated and the highway reopened by 5 a.m.
Anyone with information is asked to call PSP Bethlehem at 610-861-2026.
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