It probably surprises no one to know that the majority of accidents involving collisions between a motorcycle and a car happen at intersections – the most frequent situation being that of a vehicle turning left in front of a motorcycle.
Any intersection is potentially hazardous, whether it has stoplights, or stop signs, or is unmarked. Always check for traffic coming from the side, left and/or right. Check for traffic behind you, to make sure no one is about to run up your tailpipe.
Source: Motorcycle Safety Foundation eNews
To learn safe motorcycling skills take a course. In California the Sign-Up Web Site is: