double payne shield like used in snowmobile helmets, with a breathbox is the only way to guarantee no fog without cracking. I got a helmet for snowmobiling off ebay for $39. Breathboxes are difficult to find the right one for a "noname brand" helmet online, so I made my own out of foam that covers above the bridge of my nose all the way accross. Worked pretty good last year. Other option is FishHedz, but you won't get the warmth of a full helmet.