Yamaha Majesty 400 Clutch Spring >09 Evo Slider +15% Polini

Spring 15% harder than original

The hardness of the contrast spring plays an important role in transmitting the engine's power to the rear wheel.
It exerts back pressure on the rear pulleys and therefore has a considerable influence on the operation of the variator. The contrast spring is usually harder if the belt tends to slip, if the variator does not operate at the optimal RPM level, or if the engine, despite light weights, continues to run below the optimal RPM.
What negatively affects engine performance is a twisted contrast spring. With the Evo-Slider plate, the manufacturer Polini provides a solution to this problem.

This is a small plate that is mounted between the contrast spring and the clutch, which reduces torsion to a minimum. In addition, the Polini Evo-Slider absorbs pulley vibrations at high RPM.
The result is a smoother engine and better transmission of power to the rear wheel.
The thicker the diameter, the harder the contrast spring.

The kit includes a harder spring and an Evo-Slider spacer.
The Polini Evo-Slider allows the spring to rotate, which significantly improves the Maxiscooter's behaviour when starting from a standstill and throttle response.

Valid for:
    MBK Evolis ABS 400i H2O 4T E3 2014-2016
    MBK Evolis ABS 400i H2O 4T E4 2017
    MBK Evolis II ABS 400i H2O 4T E4 2018
    Yamaha Majesty 400i H2O 4T E3 2007-2008
    Yamaha Majesty 400i H2O 4T E3 2009-2011
    Yamaha X-Max III 400i H2O 4T E3 2013-2016
    Yamaha X-Max III ABS 400i H2O 4T E3 2013-2016
    Yamaha X-Max III ABS 400i H2O 4T E4 2017
    Yamaha X-Max IV ABS 400i H2O 4T E4 2018-2020