discoloration around horizontal cylinder exhaust port

[csp808]

I tried to see if this has been discussed before but didnt see anything. So here goes Im seeing some discoloration around my exhaust ports on each head worse on the front likely due to road fling. Is this expected or an issue with engine enamel? The bike in question is a 06 s2r 800 with about 7k miles

[DarkStaR]

This is a known issue on some models.

my 05 s2r has it also.

[pennyrobber]

There are many out there were the entire head becomes discolored. I don't think there is much that can be done about it though.