Scooter variator: how it works and how it affects performance

Scooters use a variator or variomatic within the transmission. In this article, we’ll look at how it works and why it matters in terms of performance

Il variator or better change to variator it is a component generally used on scooters instead of the classic gearbox. Also called variomatic, it is a fundamental component of the transmission, but how does it work? And above all why is it important for the performance of our scooter? We will try to answer later!

Variator gearbox or variomatic: the “easy” gearbox for scooters

First of all we need to understand how a gearbox works and why it is used. The heat engine has a maximum efficiency within certain operating regimes, that is, if we want to make it work better you have to run it in a certain RPM range. The gearbox is used to always operate the engine in this range, while varying the speed of the vehicle. With a gearbox the transmission ratio is changed by coupling gears of different sizes.

The scooter’s variator gearbox, on the other hand, allows you to change the transmission ratio automatically, greatly simplifying the transmission system and therefore making it cheaper and simpler to use. The drive belt is propped up movable pulleys. These, moving away or approaching, modify the transmission ratio. To change the position of the pulleys, movable rollers are used. THE roll, as the speed increases, they are pushed outward by centrifugal force and in turn push the pulley. A spring is also used of contrast to better control the movement of the pulleys and therefore the elongation of the gear. In this way it is possible to obtain a fully automatic gearbox which adjusts according to the speed. However, this is not an optimal system, nor is it too robust, which is why it is only used for small vehicles.

The performance

Obviously the characteristics of the scooter’s variator affect performance, in particular the torque developed and the engine speed. The critical components are the return springs and the rollers. Light rollers and soft springs will tend to move faster and therefore make the scooter more responsive, but we will have higher operating speeds and very limited torque. Conversely, with heavy rollers and hard springs we will have a high torque, but less starting point. Finding the right combination of rollers and springs will allow you to optimize your drivetrain.

If you want a scooter with low revs, you’ll want to use heavier rollers and a softer spring. You will have poor acceleration though. To have a better starting point, you can use a harder spring, obtaining a higher rpm.

Now that you know how the variator gearbox on your scooter works, you can try playing with springs and rollers to obtain the configuration that best suits your needs. But be careful to get help from an expert because these are very delicate components and you risk causing damage to the vehicle or worse to the driver if you don’t know how to handle them with due care. That’s all from the engines section, keep following us!