Replace the smooth rock trap beater blades with the serrated ones, serrated feeds better. If the beater blades are set out on the beater for maximum rock protection the smooth blades won't pull it through fast enough, limiting feeding. If you CUT the beater in HAlF and could reweld it back together so the beater blades on one half would be relocated between the blade on the other half the beater would be smoother___ Kind of like a 6 cylinder compared to a 3 cylinder. Or like the 3 strand feeder chain compared to the 2 strand. Just my thoughts!!