It happened around 9:15 p.m. Wednesday, July 3 westbound near Exit 60 in Lake Ronkonkoma.
The man, Eric Garrison, was operating a 1998 Harley Davidson when it veered off the roadway and struck the guardrail, Suffolk County Police said.
Garrison, of Ronkonkoma, was transported to Stony Brook University Hospital where he was pronounced dead.
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