Take a balloon,fill it partially with ammonia and blow it up.Rub something sweet on it like honey or syrup and tape it to something.The bear will pop it,get a face full of ammonia and will never come back.
We did something similar with ghost pepper hot sauce. Didn't scare the bear away. As a matter of fact, we put half a bottle of the stuff on a piece of pizza and the bear ate the whole thing. Bears will eat ANYTHING!!! They will take bee stings in the mouth for a drop of honey. The ammonia thing might scare them off for a day or two, but they'll be back for free food.