Like It says. My 08 YZ450F is sputtering in high gear at 1/2 throttle. It almost sounded like it backfired once. I was going down an old road to get to a track and was in 5th holding it at half throttle constantly. It was spitting and sputtering and almost sounded like it backfired once. Once I moved the throttle up or down it was gone. Very Weird. Any suggestions?