John Martin Cronin, 52, was northbound and trying to pass a vehicle when the other driver changed lanes. Cronin swerved back toward his original lane, lost control of the motorcycle, and slammed into the grassy median, police said.
Cronin had broken ribs and injuries to his head and internal organs, police said.
Cronin was with a group of other motorcyclists that included 29-year-old Konrad Leis, who also wrecked. Police believe he was trying to avoid Cronin.
Leis suffered minor injuries and gave his account of the accident to officers who arrived at the scene, police said.
The highway's northbound lanes were closed for about two-and-a-half hours as police investigated. Traffic was rerouted to the Old Glenn Highway, police said.
Reach Casey Grove at casey.grove@adn.com or 257-4589.
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