The Moto Tassinari VForce4X V4X55 Reed Valve System is purpose-built for the next generation of 50cc and 65cc motocross machines. Designed specifically for KTM, Husqvarna, and GasGas mini models, the VForce4X delivers stronger mid-range power, increased top-end performance, and improved over-rev compared to the already proven VForce3 system.
Featuring a newly engineered reed cage, air guide, and reed petal combination, the V4X55 maximizes airflow efficiency while maintaining durability for competitive racing. Whether it’s for aspiring young riders or serious junior racers, this system ensures sharper throttle response and a noticeable performance boost throughout the rev range.
Compatible Models & Years
KTM
KTM 65 SX – 2009–2026
KTM 50 SX – 2015–2026
Husqvarna
Most current TC 50 and TC 65 models
GasGas
Most current MC 50 and MC 65 models
Key Features
Increased mid-range horsepower
Stronger top-end pull with improved over-rev
All-new reed cage design
Redesigned air guide for improved airflow
Advanced reed petal construction
Improved throttle response
Designed specifically for modern 50cc and 65cc motocross engines
