Brushed alloy engine covers etc

The demo R I rode was already showing signs of all weather riding and not being "loved" in that the engine covers were already dull and speckled with road grime dirt. Is there a clear coated finish on then you can Polish off if needed, or what's the best way to keep them and the alloy wheels sparkling?
I have AC50 spray for alloy but that's more for protection for storage I think as it's a bit sticky till it dries.

Suggestions/advice welcome to keep it pristine, although it won't be used in winter/salt anyway, just dry days generally.