Bike has 19.5 hrs. Running 25% VP 110 and 75% 93 pump with bel ray H1R mixed at 32-1. I ride 250B MX only and weigh 195 lbs. geared up so I'm pretty hard on my bike. Mods include FMF factory fatty w/shorty, v-force 3 and slightly richer jetting. Riding at sea level and 60 deg. Ok so now that I got that out of the way I think everything looks great except for a slight pitting on the outer most edge of the cylinder and head. Anyone know what is causing this?