How to restore titanium header browning

[zirconxi_imp]

Hi guys, when i bought my bike used, previous owner had install a R's Gear Wyvern Full system exhaust. The header are burn beautifully with some color. However, after I have used the bike for few years, the rest of the titanium header seems to be turning gold/brown and the color on the header are losing contrast. Is there a way for me to reduce the browning while retaining the color part? found some info on the internet which involve polishing everything, meaning the color part will be removed as well, which i don't want..... Hoping to find a way to restore the color like previously.

[url=https://www.rsgear.co.jp/products/161/]Products Photo from the manufacturer of the full system