Many people are familiar with Simichrome as a quality polish for plated metals, often for chrome plating. However, what not everyone knows is that it is also a very nice polish for plastic products and even for small pieces. This stuff is expensive, but worth it in my book. It is the most versatile polish I have encountered because it is just the right mixture of gentle and abrasive for finishing off pieces. Tough... but sensitive as they say.
Here is the item "before". It's pretty cruddy and faded, but not broken or heavily damaged. The reflector lens has some scratches but no breaks. I then set to work with Simichrome. I generally follow the directions, but instead of letting the polish paste haze up entirely, I actually start rubbing while it is still soft. I want to work gradually with a softer paste on plastic than on chrome plating. For chrome, I would follow the directions on the box and let it haze up. Because this is plastic, I suggest working it while it's still soft.
Here is the side of the piece after working. There are still some of the deeper scratches, but as you can see it's much better. Some of the fading has also been removed. If you wanted to go after those deeper scratches, or entirely remove the faded layer, you would have to keep working with the polish. However, you have to remember that you're removing material with each pass. The Dawn will be a "cleaned up" but not totally done over bike, so some minor wear like this is fine for me.
Here is the finished piece overall. As for the lens, I polish that too. I put on the Simichrome and again work it while soft. This time I am careful to take some pressure off and work in circles, lightly swirling around. The result is that the reflector cleans up pretty well, though a few scratches remain. Once again, that sort of condition will work fine with this 1965 Raleigh Dawn roadster, so I'm happy enough with the result. The hardware you happen to see with it will be cleaned using a Dremel brush rather than Oxalic acid because CAD plating and galvanized finishes are attacked by Oxalic. The Dremel brush will be the answer for those. I am getting to the point where I should start buying stock in Dremel's company, since I use so many brushes and attachments these days.