As I dive further and further into blacking my bike out, I have tried several different types of paint and powder coat. Here is some of my experiences, as they may help you.
First off, don't let anyone tell you any different, powdercoat is the way to go. However, if your like me you don't have any spare time to have your parts sitting at a powdercoating waiting to be done, and have a good enough memory to put your bike back together how it came apart when the parts arrive. One option is buying parts already powdered, but why buy more parts when the ones you already have on your bike are good enough. So, next option is paint.
I have used 3 different kinds of paints so far, and here are my findings. For high heat, up to 2000 degrees I used Rust-Oleum High Heat flat black. This is a rattle can, and is about $8 a can at your local auto parts store. This stuff really is flat, and doesn't match the satin look of the Harley Denim black. However, its holding up great for me on my head pipes and muffler. Time will tell on how durable it is,.. but the plus side, touch up is only a spray away with the rattle can. Just imagine your BBQ grille,.. this stuff is flat flat black. Cool contrast to the rest of the bike, which I like some contrast here and there to break it up.
On my primary cover, shift linkage, horn cover and air cleaner cover I used VHT High temperature Wrinkle plus. This stuff is good for 350 degrees, but takes some practice before you can lay it down really smooth. Its kind of finicky on how think you get it, and the thickness is what causes it to wrinkle. The wrinkles are rather large compared to the engine cases, but my HD derby matches up well with the primary that I painted. This stuff can be found at most auto parts stores, and is abut $9 a can.
The best stuff that matches up almost perfect,.. John Deere Blitz black. Again, I bought the rattle can. This stuff is $8 at your local John Deere dealer, and quarts are only $28 if your wanting to do a lot of stuff (keep in mind you need reducer and a spray gun). Right now, I am painting a few parts, and will post pics when they are done to show how close of a match the paint is. I don't think this stuff is made for high heat, but I may try a few engine parts to test it out. So far, I can't tell the difference between whats been painted using the John Deere paint, and what was painted by Harley.
***UPDATED with pics***
This first example, is the wrinkle finish paint. Notice how its more wrinkle then the engine, but mathes up perfect with the wrinkles on the HD derby cover (which I did not paint). You can also see some of the high heat flat black on the top transmission cover. Its a little off from engine, but you can't really tell in person, the flash really makes it look different.
Number 2, the John Deere blitz black on the strut covers. These babies are almost dead on. From seeing this paint, and the paint that came on my hogg chopps, I think they must use the same paint because they match perfectly, which has a little more sheen to it then the Harley denim black.
A shot from the side, but this angle with the flash makes them look totally different. This picture worried me at first, but look at the picture above, and see how different my saddlebags look from the fenders... see, camera trickery! It could also be the dust from sitting in storage.
From the side, showing the pipes and muffler painted in the high heat flat black.
I can also give some tips, or a tutorial on how to prep your parts for paint if anyone is interested. I have been painting chrome for a while with no problems.