It happened around 6:15 p.m. Sunday, Sept. 8 in Centerport, Suffolk County Police said.
Robert Gaydes, 27, of Huntington Station, was riding a 2008 Harley-Davidson motorcycle northbound on Centershore Road, near East Main Street, when he apparently crossed over the divider and collided with a southbound 2003 Ford pickup truck, said police.
Gaydes was airlifted by Suffolk County Police helicopter to Stony Brook University Medical Center for treatment of serious injuries.
The driver of the pickup truck, George Pryor, 16, of Centerport, was not injured, according to police.
The vehicles were impounded for safety checks. Detectives are asking anyone with information on the crash to contact the Second Squad at 631-854-8252.
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