Hey guys my 400ex is cutting out above 3/4 throttle. When I first bought it, it would pop sometimes at full throttle but quickly got worse and just doesnt even fire above 3/4 throttle. It currently has some bad valve stem seals and burns a lil oil (getting fixed tomorrow), but it runs perfect up until you give it alot of throttle. Its got a new spark plug and a white bros rev box, so is it maybe just a dirty carb? Never messed with a 400ex carb before so I thought id get your guys advice before tearing it apart.