It happened around 3:25 a.m. Saturday, Aug. 6 in Cold Spring Harbor.
The man, identified as Jeramy Reiderer, age 30, of Seaford, was operating a 2017 Yamaha motorcycle westbound on Route 25A, when he lost control of the vehicle, which struck a guardrail near Route 108, Suffolk County Police said.
Reiderer was airlifted to Stony Brook University Hospital for treatment of serious injuries, said police.
Detectives are asking anyone with information on the crash to contact the Second Squad at 631-854-8252.
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