Honolulu police say a 41-year-old man has died following a solo motorcycle crash on Wednesday night in the Waipahu area.

Police said at about 10:40 p.m., the motorcyclist was traveling northbound on Fort Weaver Road when he traveled onto the Waipahu off-ramp at a high rate of speed and lost control. He collided with a metal lamp post and was thrown onto the roadway.

Emergency Medical Services transported the man to a hospital in critical condition, where police say he later succumbed to his injuries and was pronounced dead. He was not wearing a helmet at the time of the collision.

At this time, speed appears to be a factor, while alcohol or drugs remain unknown as factors, in the collision.

Police said this was Oahu’s 39th traffic-related fatality this year, compared to 36 during the same time last year.

An investigation is ongoing.