My AB Mods Team driver Brian Dunbar who is also sponsored by Team Orion came by today with the new US Spec Team CRF .21 engines. They have made some changes on the engine such as sleeve port timing, crank timing, venturi, and a new drilled/lightend cooling head. So I'm going to break them in and do some dyno testing etc. I snapped a few quick pics of the engine, so here is a sneak peak of the new Team Orion "US Spec" CRF .21 offroad engine!