Half-pulley of Variator Malossi d.107mm Piaggio Scooter 50 2T

Malossi Ventilvar 2000 fixed half-pulley Ø107 mm 14º for Piaggio Scooter 50 2-Stroke engines.

The fixed half-pulley forms one of the two faces of the front pulley of the CVT transmission. When the rollers move the movable half-pulley, both faces come closer together and force the belt to operate on a progressively larger diameter, lengthening the transmission ratio as RPM increases.

In this Ventilvar, the outer diameter of 107 mm defines the available surface for the belt travel, while the 14° angle determines how the side of the belt rests on the pulley. This geometry is important because it affects contact, pressure on the belt, and its movement throughout the entire variation range.

In a transmission, it is important that the belt can rise uniformly to the outer area of the pulley without encountering irregularities, steps, or damaged surfaces. Any wear on the track can alter the ratio, generate heat, and cause uneven wear on the sides of the belt.

The Ventilvar design also incorporates cooling fins on the outer face. As it rotates together with the crankshaft, these fins help move air inside the transmission case, reducing heat buildup around the Variator, belt, and CVT assembly.

This is especially important in tuned engines, where the transmission operates for longer at high RPM and with greater load on the belt. Excessive temperature can alter the behavior of the belt material and accelerate its degradation.

During installation, we especially recommend checking the width and condition of the belt, pulley surfaces, Variator bushing, rollers, and maximum transmission travel. In a Racing setup, marking the pulley faces makes it possible to visually check how far the belt is rising and verify that the available diameter is being used correctly.

Technical specifications

• Manufacturer: Malossi.
• Range: Ventilvar 2000.
• Product: ventilated fixed half-pulley.
• Outer diameter: 107 mm.
• Track angle: 14°.
• Engine: Piaggio Scooter 50 2-Stroke.
• Application: CVT Racing transmission.
• Compatible Variator: 5115644 / 5118238.

Important: installation of this half-pulley requires removing the electric starter system. This is a configuration intended for Racing transmissions where the operation of the Variator, pulley, and belt assembly is prioritized over maintaining the original starter system.