Same way you'd paint a plastic bumper on a car is my guess. All Treks are painted and it seems as good a job as you'd ever hope to see--even including the slight metalflake look--but do not know about heating--it's probably just a good acrylic paint that is applied under controlled conditions, e.g., 75-80 degrees. I've never had a worse powder coat paint job (from the factory) than was on my old Y2K Lemond Zurich, whereas the paint on '01 BA is like iron.