The device of a variator on a scooter

The variator is a modern PPC device, and itsapplication in various techniques with each passing day is gaining popularity. The mechanism of a variator box on scooters is very simple: its developers were based on the action of centrifugal force, and they achieved the ease of construction.

The components of the variator

The scooter has a small mass and dimensions (compared to motorcycles and cars), respectively, and the gearbox must be small.

From the car, the scooter variator inherited:

• two pulleys - leading and driven (though here they have a wedge shape, and each consists of two halves);
• belt (its shape is trapezoid, in contrast to the car).

That's the whole legacy.

The position of the wedge-shaped halves (cheeks) of the drive pulley are adjusted by the rollers. The central spring, connected to the clutch, opens and closes the cheek of the driven pulley.

More about the principle of work

So... Scooter is running and running at idle. What happens in the variator? The drive pulley rotates at minimum speed. The belt is located just above the center of contact of the cheeks. The slaves of the follower are compressed by a central spring. The belt on them moves along the maximum radius.

The scooter moved. Here it is worth mentioning videos. They are located behind the inner cheek of the driving pulley. When the speed of rotation of this pulley increases, the centrifugal force pushes the rollers to the outer radius, thereby squeezing the halves of the driving pulley together. The belt between these halves shifts outwards - the radius of its turn on the leading cheeks increases.

The driven pulley acts exactly the opposite. During speed dialing, the centrifugal force acts on it, just like the rollers, with the help of which the cheeks move apart, compressing the central spring and passing the belt between them. This is how the overclocking takes place.

Due to this synchronous operation of the pulleys, the speed set occurs at a constant speed and maximum engine power.

Adjustment of a variator on a scooter

Adjustment of the variator achieves the desired dynamics of the scooter. It can be improved by replacing both factory rollers and springs.

The work of the rollers on the scooter variator depends on theirweight. The manufacturer selects the optimal when collecting the box. But fans of fast driving change them to heavier ones. With heavier rollers, the scooter with the variator is slower to accelerate at the start, but after a set of maximum revolutions the engine produces a speed of 10-15 km / h more than with the factory rollers.

Using smaller rollers leads to the opposite principle: the scooter starts abruptly, but it's hard to reach the maximum speed.

Changing the spring stiffness also affects thespeed. Stretched and weak, it can not tighten the cheeks of the driven pulley. This will cause the belt to work continuously on a smaller radius than necessary. Too tight a spring, on the contrary, will not reduce this radius (accordingly increase the speed of the driven pulley) and develop the maximum speed of the scooter.

Repair of a variator on a scooter. Substitution of elements

Changing the speed of acceleration and the appearance of extraneous noise in the variator indicate that some part (or parts) is worn out and requires replacement.

To find out the cause of the malfunction, follow the variator:

1. Remove the cover. Do it carefully so as not to damage it. As a rule, the cover of the variator on scooters has a gasket. It is necessary to assess its condition and, if necessary, change it.
2. To remove the belt from the variator, you need to remove the drive pulley. And you can get to it only by removing the lock ring, clutch and gear.
3. When the belt and the pulley halves are ready, we remove the rollers.
4. All elements must be carefully inspected andchecked. Proper cheeks have a flat surface without chips and scoring. The belt excludes the presence of any lubricants. If it looks messy, then it's time to change it.
5. After troubleshooting, we collect the variator in the reverse order.

There are two main features on whichthe quality of the variator is determined: the movement of the belt and the engine speed. In the working variator, the belt does not slip in the pulleys. But, if the engine screams and the scooter does not go - this is the first signal that it's time to look inside the device and examine the condition of the belt and the spring.

The engine's working speed must correspond to the revolutions of its maximum power. If this does not happen, it's time to start tuning the variator.