The gold and blueing is caused by extreme heat on the exhaust. This happens with a lot of people. Mostly people leave their bikes running too long before they take off. With no air flow to cool the chrome down, it turns colors.
One thing you can get is Blue Away. It's this polish stuff that'll actually remove the coloring from the chrome. Keep in mind though, that this stuff actually works by removing an ultra-thin layer of the chrome, so you can get away with it a few times, but you wouldn't want to do it once a week. Also, you'll want to hit that chrome with a standard polish afterward, to keep it shiny