The engine appears to be a transplant from an old craftsman snowblower. You will need to change the throttle control to one for mini
bike use and add an air cleaner. CFH wrote an excellent thesis on this subject, find it via links to his postings.
Pay particular attention to the condition of the inside of the metal tank. It must be clean and free of any loose or flaking rust, if not it will clog a new or freshly rebuilt carb in short order. You should replace the fuel line too.
Good luck with your project