A 29-year-old man died today after crashing his motorcycle on the 'Ewa off-ramp of the H-1 Freeway in West O'ahu, police said.

The Honolulu Medical Examiner's office identified the man as George Casher of 'Ewa Beach. Casher was pronounced dead at The Queen's Medical Center at 1:02 p.m. An autopsy is scheduled tomorrow to determine cause and manner of death.

Police vehicular homicide supervising investigator Sgt. Danny Kaholokula said the 11:45 a.m. crash involved a 2005 Yamaha YZF-R1, which witnesses stated was speeding past vehicles in the left lane on the off-ramp.

The motorcycle veered off the offramp roadway, 946 feet west of the H-1 Freeway, ejecting its operator, according to Kaholokula.

The operator suffered critical upper torso injuries when he struck a steel directional sign post, said Kaholokula. It is unknown if the operator was wearing a helmet, he added.

The death is O'ahu's 30th traffic fatality of the year and fifth involving a motorcyclist. In 2007, motorcyclists accounted for 15 of O'ahu's 68 traffic deaths.