Moto Tassinari VForce4R V4R04 Reed Valve Yamaha YZ125 2005-2017

The unique design of the V-Force 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 V-Force advantage. Since the petals are only traveling half the distance, they generally last longer and they receive less wear than the reed petals on a conventional reed valve design. - 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. -Rubber overmodling on reed tip surface of cage to further enhance petal life. -All-new manifold, reed cage and air guide designed for the VFVorce4R.