(Portland, OR)  --  Police are releasing the identity of a motorcyclist who was killed in a crash Monday afternoon.  Police say 35-year-old Nathaniel Entriken hit the passenger side of a car at the intersection of Northeast Ainsworth Street and Grand Avenue.  Entriken died at the scene.  Investigators say the motorcycle was stolen and speed was a factor in the crash. The driver of the car wasn't hurt and remained at the scene.