CHACKBAY — A Thibodaux man died Monday after a car rear-ended his motorcycle on La. 20 in Lafourche Parish, State Police reported Tuesday.

Louis Ledet Jr., 43, was thrown from the 1998 Honda motorcycle shortly before 8:58 a.m. Monday west of Appletree Drive, troopers said in a news release.

Ledet, wearing a skull cap-style helmet not approved by the U.S. Department of Transportation, troopers said, was pronounced dead at the scene.

Witnesses told troopers the motorcycle was speeding up and slowing down before it was hit, troopers said.

Toni Aucoin, 30, Thibodaux, the driver of the 2009 Infiniti G 37 that hit Ledet, received minor injuries in the crash and was taken to Thibodaux Regional Medical Center, troopers said.

Alcohol or drug involvement is not suspected, troopers said.