Christopher Thompson of Los Angeles, a 60-year-old physician, was also convicted Monday of battery causing serious injury, reckless driving and mayhem in the July 2008 incident.
Police say Thompson argued with the bikers on a narrow road before he slammed on the brakes in his red Infinity.
One of the bicyclists dislocated his shoulder. The other broke his teeth and has scars on his face.
Thompson could face 10 years in state prison.