As you know, the finned "cylinder heads" are simply painted silver by Kymco; so after removing them from the bike, I took a Scotch-Brite pad and rubbed off the silver paint from the fins (just the ends of the fins, not all the way down each individual fin!). I cleaned the parts with acetone, then spray painted them with "Low gloss black" engine paint from Pep Boys (an automotive parts store). After the paint had dried, I carefully rubbed the black paint off the ends of the fins and polished them with an aluminum polish. The rest of the engine was painted with the same paint, but I had to lightly sand and scotch brite the whole thing, clean and mask off the frame, radiator hoses, and wiring. Short, controlled blasts of paint from different angles eventually covered the whole engine. Preparation was key.
The frame was red; some portions were spray painted gloss black, while others were simply brush painted with Rustoleum from a quart can.
