_Burnt red plug sounds like it’s burning transmission fluid. I think Linda (mycider) had that problem with her Tomos._
Indeed I did. From my research back then though, I believe that the red plug could also be attributed to rust in your gas tank, certain fuel additives, and old/bad gas. I had all of those, but the red plug color stuck around after I fixed all of that, and it went away after I replaced the bad crank seal. Does your moped produce copious amounts of white smoke?