A 36-year-old San Ramon died Sunday when his motorcycle left the road and crashed into a tree off of Interstate Highway 680 in Alamo, according to the California Highway Patrol.
Officers responded to a report of an accident at northbound Highway 680 at Stone Valley Road around 1:30 p.m., arriving to find Daniel Basso of San Ramon dead, not far from his 2003 Yamaha RS motorcycle.
Officers said Basso left the roadway for unknown reasons and struck a tree.
Both the on and off ramps from Stone Valley onto I-680 were closed as officers conducted their investigation. Traffic was allowed through the area at 2:30 p.m.
Anyone who witnessed the crash is asked to call the CHP Contra Costa area office (925) 646-4980.