Okay, since we are on to a fling cleaning thread jack, I would like to add that I've found the cleaner/wax products like the ones from Honda and Plexus really do the trick. They take off everything from chain spray, road grim and bugs leaving a super slick wax based shine. The Honda spray is much cheaper and I think they both work the same.
Plexus Plastic Cleaner
Pro Honda Spray Cleaner Polish