From working on cars, it will smoke a little. You might also have a little leak unless it smokes when the exhaust is hot and the bike is off. You can normally tell by how it smells, if it is chemical smelling then it is paint. If it is oilly, or a gas type smell then it is an exhaust leak.
Did you paint a factory exhaust or an after market exhaust? Did you use a high temp paint? If it is not a high temp paint it will be smoking and burning off all the time. If the pipe was a factory chrome pipe and wasn't preped right it will burn off as well.