My one year old is a biter. We try to redirect him from biting. He is a little young to really explain to him much. But definitely knows no biting. We have taught our older son, who is three to push him away when he is going to bite, and get away from him. In your case, you may be able to explain a little better about biting. Not only is it not ok, it hurts. Teach him other ways he can release that excitement and energy. Or else cut him off from the situation or circumstance when the level of emotions is getting risky until he is able to have some self-control. I know this is difficult and trying, but you really can prevent a lot of hurt(including physically with bruises and cuts etc) in the long run.