http://www.gofasters.com/productdeta...atalogId=-2231
I originally had these on a Cannondale 440, which would boil if you stared at it too long. These, a fan, and waterless coolant made it ridable in the woods. A little pricey now at $45. The GG 2stroke is probably the most boil resistant bike there is stock, so if you have no issues I'd pass. Try waterless coolant as well if you boil at altitude. I just have them so I use them.