stains

I noticed the other day, while checking my oil level, that the yamaha belly pan inside had some strange stains.. I am not sure if it is oil or grease, or something like that.. But definitely it is not dirt from the road.. Have you noticed anything similar.. By the way the oil level was where it...

I noticed some black stains on the silencer of my exhaust.. Is it just gas and water? Or is it something i need to start worrying.. Do you notice something similar with your exhausts? Just checking..