I have a Saito 100 I bought used to rebuild. the owner was very happy to tell me he always ran it slobbering rich. I question that to myself. when I took it apart I found the valves were thickly cacked fuzzy black. the cam too, but not as bad. the cylinder liner was stained black.
the piston skirt was blistered a bit and the ring look to be eaten by acid. I considered this to be caused by setting too long in burnt oil.