The crash happened in Hartford County in the eastbound lanes near Exit 34 in Plainville at about 9:50 p.m. on Sunday, Sept. 25, Connecticut State Police said.
A 2011 Harley-Davidson FLHX was traveling in the left center lane when, for unknown reasons, it swerved into the left lane and sideswiped a 1993 Lexus LS 400, police said.
The impact caused the motorcyclist to lose control, traveling across the left lane into the left shoulder and crashing into the concrete barrier, according to the report.
Authorities said the motorcyclist, a man from the Windham County town of Ashford, was thrown from the motorcycle, suffering serious injuries in the crash.
He was taken to the hospital for treatment, police said.
The driver of the Lexus, a 31-year-old Bloomfield man, was not injured, authorities said.
Both vehicles were towed from the scene due to disabling damage, police reported.
Police asked witnesses of the crash to call Trooper Michael Dean at 860-534-1098 email him at michael.dean@ct.gov.
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