Dave Briggs, 36, was traveling east on U.S. 20/26 near McDermott Road in Meridian at 11:28 p.m. when he lost control, struck a concrete barrier and was thrown from his 2004 Buell motorcycle.
An Idaho State Police trooper saw Briggs as he crashed his motorcycle. The trooper said Briggs was speeding at 66 miles per hour. The speed limit on that portion of the highway is 45 mph.
Briggs was taken by ambulance to St. Luke's Regional Medical Center in Boise.
The eastbound lane of the highway was blocked for approximately 45 minutes.
The crash is under investigation by the Idaho State Police.