A 28-year-old Big Island man died yesterday from injuries suffered in a motorcycle crash on Kapuna Street in Kailua, Kona.

The man was operating a 2007 Harley Davidson and traveling north on Kapuna Street when he hit a curb and was thrown from the motorcycle. The man was not wearing a helmet.

Kona police responded at 3:35 a.m.

The man was taken to Kona Community Hospital and pronounced dead at 5:05 a.m.

Police suspect speed, alcohol and drugs were factors in the crash.

Police are not releasing the man's name until his identity is confirmed and next of kin notified.

Traffic Enforcement Unit officers initiated a coroner's inquest case and ordered an autopsy.

The man's death is the Big Island's 13th traffic fatality this year, compared with 14 on the same date in 2006.