cleaning my top end

[SET THE STAGE]

so i've been working on getting my motor nice and black again, but on my topend there still seems to be spots all over it where like the dirt just won't come off. like you know how the stock jugs are kind of rough feeling, well there's like dirt stuck in it and it's making it look bad

how could i go about cleaning it without taking any of the paint off?

[Dave83]

Simple Green and a toothbrush.SG is about the best "gentle soap Ive found.I use it on my gear also(works wonders on white boots).