Wayne is right.
You have some problem, and it may be causing performance issues, especially if it is a 2 stroke.
You need some sort of resonance on a 2 stroke to make it work properly. With a leaky exhaust, you lose this backpressure as well as make the bike run lean, plus it makes em sound like crap.
If its a 4 stroke, its going to get real crappy gas milage, and the heat doesn't disipate properly.