Polishing stainless steel exhaust headers

[Thorsten]

Hi all, I was trying to polish a set of custom bent SS headers for a motorcycle today. The tubing probably had the mill finish on it, kind of a dull grey. When I started working it, starting with 180 greaseless compound on a sisal wheel, it took off the grey, but revealed a kind of rough surface, lots of tiny pits everywhere that didn't go away as I worked my way through 240 and 300 greaseless on sisal, then black emery on spiral cotton, and finishing with white compound. The final result is pretty shiny, but it's definitely not a mirror shine like chrome.

Any ideas? Or is SS so hard that with DIY tools (I have a 1/2 hp electric motor) it's not possible to achieve a mirror finish?

Any advice greatly appreciated.

Thorsten