If you are getting smoke out of that pipe what color is it? If you have an
oil leak it should be a bluish color. Water could cause it to be whitish. And as JHV48 said, feel the inside of the pipe and see what it smells like. I doubt if the carb is any problem as it would normally affect both sides and the pipes would be very black and wet. Good luck and I hope it isn't anything serious.
Ron