Yes the bike is running rich, but there is still an exhaust leak that should be addressed. As far as adjusting your jetting, you will need to pull the carb, remove the jets, and including the needle jet. Once you have all the jets out, please write them down... Many do not, and have no idea as to what their running. Once you have a list of the jetting, we can help you with a leaner set-up. Most likely your fix will be changing the needle clip one position .
Pull the carb, give it a proper cleaning, and write down current jetting. While you're there, change out the rubber on the exhaust with a peice of a radiator hose and give everything a good cleaning. Come on back with your current jetting specs and we'll get you straightened out.