i ride dirtbikes also so i have a kickbutt full face helmet and can use goggles, but i also see most of you guys use full face with a flip down sheild, my question is dont those sheilds fog ? im thinking my dirtbike setup may be a bit chilly also. so should i get one of those sheilds and how can i keep it from fogging?, just trying to get some input before i plunk down some coin on a helmet for sleddin