Maximizing Your Yamaha YZ250 & YZ250X Performance: V4X07EM The VForce4X Reed Valve System

Maximizing Your Yamaha YZ250 & YZ250X Performance: The VForce4X Reed Valve System

Maximizing Your Yamaha YZ250 Performance: The VFORCE4X Reed Valve System

Moto Tassinari - History:

For over 25 years, Moto Tassinari has been a renowned name among two-stroke engine enthusiasts, known for their strong dedication to performance. Moto Tassinari's main product is the VForce reed valve system.  With twice the reed-tip area compared to typical systems, it's a favored performance option for those seeking to enhance the power of their 2-stroke engines. The latest model, the VFORCE4X, is now on the market, specifically designed for Yamaha YZ250 and YZ250X motorcycles, with the goal of elevating performance to new heights.

he all-new VFORCE4X for the Yamaha YZ250 and YZ250X V4X07EM

Durability Meets Performance:
The VFORCE4X V4X07EM - is designed to overcome the usual limits of the standard reed valve system. It's highly durable, which means it lasts longer, enabling riders to use their bikes more rigorously and for an extended period. This strength does not diminish its performance; in fact, it enhances it. Riders experience a sharper response when applying throttle, accompanied by a stronger flow of power.

Improved Efficiency, Unmatched Throttle Response:
The Moto Tassinari VForce reed valve system is characterized by its simplicity, owing to its straightforward and effective design.  The VFORCE4X enhances engine power and throttle response by increasing the surface area of the reed tip. This results in more power at low-end, a stronger mid-range, and greater power at the top end to enhance over-rev capabilities. By increasing the reed surface area, more air can flow through, ultimately creating more horsepower.

Redefining the Reed Valve:
Moto Tassinari focuses on innovation with the VFORCE4X. This product is an upgrade from the VForce3, which has been a standard for 15 years. The VFORCE4X includes new components such as a manifold, reed cage, and air guide. These improvements aim to boost power and durabilty. Riders report that VForce reeds sharpen jetting, especially at low speeds, leading to a smoother power transition.

The Verdict:

The VForce4X is compatible with other performance upgrades such as exhaust pipes, silencers, and cylinder porting to further enhance their performance.

The VFORCE4X shows Moto Tassinari's dedication to top-notch two-stroke engine performance, perfect for racers and enthusiasts who want the best from their bikes.


The all-new VFORCE4X for select GasGas, Husqvarna and KTM TBI fuel injected 125/150/250 and 300cc motorcycles V4X26AM

Other fitment options (KTM, Husqvarna, and Gas Gas):

The all-new VForce4X V4X26AM - for select GasGas, Husqvarna and KTM TBI fuel injected 125/150/250 and 300cc motorcycles has been designed to offer you exceptional durability and overcome the short comings of the stock reed valve system.

**Fits all fuel-injected TPI and TBI models. Does not fit 2024 TBI oil-injected** models.

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