A Cheyenne man died in a motorcycle crash south of Manville on Thursday afternoon, according to a news release from the Wyoming Highway Patrol on Monday.

James Barth, 37, was riding a motorcycle traveling northbound on Wyoming Highway 270 in Niobrara County, according to the news release from Patrol Sgt. David Wagener.

About six miles south of Manville, Barth entered a left-hand curve and the motorcycle left the highway and struck a delineator post. He was thrown from the motorcycle down a steep embankment.

Barth was not wearing a helmet and died at the scene, according to the news release.

The Wyoming Highway Patrol is investigating operator inexperience and inattentiveness as contributing factors in this crash.

This marked the 39th highway fatality in Wyoming for 2016. There were 64 fatalities during this same time period in 2015.