for V‑Force 4R Reed Valve System More Horsepower Maximum Air Flow V4R04 for YZ125 2005‑2020 Item Type: Reed Valve System Material: ABS OE: V4R04 Fitment: Fit for YZ125 2005-2020Description:The unique design of the reed valve system features double the reed tip surface over a conventional reed valve design. This has two major benefits: 1) The reed petals only travel half the distance as a conventional reed valve design to get the same airflow. 2) Because the reed petals only need to travel half the distance of that on a conventional reed valve design, there is a greater chance of them being fully opened as well as a better chance of sealing when they are closed. A reed petal never truly closes in a classic sense, as it is always in movement. Consider this, an engine operating at 8,000 RPM results in a reed petal opening and closing 133 times in one second. This fact, sheds light on another advantage. Since the petals are only traveling half the distance, they generally last longer are they receive less wear than the reed petals on a conventional reed valve design.Fine Workmanship:Double the reed tip surface over a conventional reed valve design. Increased bottom end, stronger mid range and longer top end. Greater efficiency due to reduced reed petal travel. More airflow means more horsepower. Reduced reed petal wear. Screw free design eliminates risk of screws going through motor. Screw free design enables super quick reed petal changes. Characteristic:All new reed petal resin system, carbon fiber and lay up. Pre curved reed petal ensures better seal at tip. Wider reed cage for maximum airflow. Combined reed tip area increased by 10.5% resulting in increased total air flow. Airfoil shape added to cage tip to increase air velocity from outer ports. Long reed stops added to progressively slow petal tip velocity, for increased petal durability. Reduced frontal area of central wing by 15.6% combined with a more aerodynamic shape