The distinct ring of mud left on your tires after driving into a remote area to have sex in your vehicle.
by mr sparky March 14, 2016
motocross term for perfect mud. theres "sex mud" "fun sex mud" and "gross sex mud" its when the mud is so great for riding that you could just have sex with it! "sex mud" is good for racing, "fun sex mud" is good for messin around and tearin up the ground, and "gross sex mud" is really dirty sticky mud that gets everywhere
by dirtbikeking May 30, 2009