There are movies about everything, even motorcycle riders. While some movies might feature a character or two who ride motorcycles, they may not focus entirely on that. Often, motorcycles are used in the movies or on television for two things: to indicate someone who is a rebel or for the main hero to ride when he or she is doing something badass or risky. For example, car chase scenes are cool, but when the hero is chasing down the bad guys on a motorcycle, they're downright awesome.
Motorcycles are also a very easy way for filmmakers to let us know that a character is a rebel, a troublemaker, or refused to conform to society. Whenever we see someone ride up on a bike and take his or her helmet off, we immediately know they're going to shake things up and maybe even cause some trouble! The fact that they usually wear leather jackets with sew on patches on them further confirms that they're rebels!
But movies haven't always been kind to motorcyclists. One of the earliest movies, The Wild One, led to a lot of controversy over bikers. The film follows a group of 'outlaw' bikers who visit a small town in California and proceed to terrorize it. By the time the movie's over, the town has been trashed. It doesn't portray bikers in a positive light at all, and this movie is one of the major reasons bikers have such a reputation as outlaws. However, the performance of a young Marlon Brando as biker Johnny Strabler has been praised, so even though these bikers don't reflect how true motorcycle riders act, it's still worth watching.
There are many other movies featuring motorcycle riders, and they're all worth a watch just to see how Hollywood sees bikers.