Mackenzie Brennan, of Pennsylvania, was headed northbound on County Road 517 when his Kawasaki overturned just after 5 p.m. Tuesday, New Jersey State Police said.
The bike struck a guardrail ejecting the driver at milepost 24.8, NJSP said.
Brennan was airlifted to an area hospital with serious injuries, but was stable as of Wednesday morning, according to NJSP.
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