Police said later Tuesday that the officer was walking and talking and his injuries were considered not life-threatening.
The crash happened shortly after 3 p.m. on the southbound side of the freeway, near Barton Road, according to the San Bernardino County Fire Department. Whether any vehicles besides the motorcycle were involved was unclear.
All southbound lanes except one were closed while crews worked to clear the scene.
The cause of the crash is under investigation.