BOYESEN DIRT BIKE PRO SERIES REEDS. Pro series dual-stage reeds combine a carbon-fiber top reed with a fiberglass bottom reed for unrivaled performance. The Pro Series are more responsive than our traditional power reeds. The carbon-fiber top reed has excellent response characteristics that provide even quicker acceleration, stronger throttle response, and more over-rev than our standard power reeds. The fiberglass bottom reed provides stability and longer reed life.