It happened at 11:45 p.m. Friday, June 24 in Lindenhurst.
John Krug, age 27, of Lindenhurst, was operating a 2000 Harley Davidson motorcycle westbound about a half-mile east of Exit 37, when he struck the attenuator attached to the rear of a 2014 Hino flatbed truck, Suffolk County Police said.
The flatbed truck was in the left lane blocking traffic for roadwork, police said.
Krug was airlifted to Stony Brook University Hospital for treatment of serious but non-life-threatening injuries, police said.
The driver of the flatbed truck, a 62-year-old Bay Shore man, was not injured.
The motorcycle was impounded for a safety check. The flatbed truck was inspected at the scene by officers from the Motor Carrier Safety Section.
Detectives are asking anyone with information on the crash to contact the First Squad at 631-854-8152.
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