Okeydoke, got a bit of time this evening and got at it with a bit of steel wool and some penetrating oil. First I sprayed down the burned on oil or whatever it was with penetrating oil. Carb cleaner just dried off and didn't touch it. The spray oil soaked in and the steel wool started working on it as well. After a bit I wiped it down with a paper towel and then repeated the process. Bit by bit I moved down the pipe and the chrome started coming out of the goop. I've got probably 90% off now, with all visible parts of the pipe nice and shiny again. After thinking about the suggestion of steel wool I got to thinking about the different rusted firearms and pellet guns I've managed to salvage over the years. For light rust a bit of light oil and steel wool does the trick, as long as one doesn't get TOO enthusiastic with the elbow grease. Well, it worked a treat on the chrome as well! Now to get the bike washed so it's presentable again... Thanks, heloego, for the suggestion!