For many novice motorists, sometimes it’s not easy to choose their own wheels for their iron friend. All because their labeling reflects a large number of parameters and characteristics. This article will discuss the method of decoding the size of the disk and choosing it for the car.
Reading specifications
The entire line of parameters printed on the disk can be divided into several components. It might look something like this: 7jx16 H2 5x130 ET20 d74.1. To decrypt the size of the disk, you need to consider each element in order.
It is worth noting that sometimes the location of the parameters in the line can change places and differ slightly in characters. But the general algorithm for decrypting disk sizes on a car is always the same.
Width
The width of the disk is indicated in inches and is the first in the line of characteristics. In fact, this is one of the determining parameters when choosing. Based on this value, in the future, the tire width will be selected. Examples of marking: 8.5 12, 9.5.
Experienced drivers claim that a large width significantly affects the handling and dynamics of the car.
Marker design side racks
Immediately after the number with the width of the disk is the letter value. As a rule, for a motorist it carries little information and is used mainly by service specialists. In most cases it is marked with the letter J. But there may be JJ, K, JK, B, P, D.
Disc diameter
In deciphering the dimensions of the disc, the design symbol for the side flanges is followed by a numerical value of the diameter in inches. It is also one of the main parameters. Changing the diameter of the disk in a larger direction can change the size of the used tire. And this, in turn, will affect the handling on the highway. For example, on low-profile tires, all the roughness of the road will be clearly felt, and all the load will fall on the suspension shoulders.
Humps
Next in order is the designation of the humps. These are the protrusions along the flanges, which allow you to more securely mount the tire. They can take the values H, H2, X. Here H is a regular hump, X is a truncated one. The coefficient after it is the number of parties on which the hump is located.
PCD
The next parameter is sometimes called PCD. It is labeled something like this: 5x130. The first digit in the record shows the number of disk mounting bolts, and the second is the diameter on which they are located in millimeters. This is one of the most important parameters when decrypting disk sizes.
Values can vary in very small ranges, reaching tenths of a millimeter. Therefore, if the characteristic is not selected exactly, there is a possibility that the bolts will not be able to fall into place. As a result, the fasteners will not be tight. So, then you will have to carry out frequent balancing and repairs.
Departure
This parameter consists of numbers and letters. Maybe this is ET20. In short, it means the distance between the plane of the disk and the axis of symmetry. May be negative and positive. The first option will visually make the disk more convex relative to the car. The second is in-depth.
A significant change in the ejection of the disk affects the displacement of the steering axis, increases bearing wear and, in some cases, worsens handling. Auto manufacturers strictly regulate the size of the allowable departure and roughly violate it - it means hitting some parameters of the car, which may worsen.
Diameter of center hole
Measured in millimeters and indicated by letters and numbers. For example, d85. When decrypting disk sizes, you should pay special attention.
Extra options
When decrypting disk sizes, other characteristics can be used. For example, the maximum load on the disk. Passenger cars use wheels with a margin of safety, which should be sufficient for its needs. But if it turns out that it will be rearranged to a different type of equipment, for example, an SUV, then the nearest small hole can damage the disk.
Usually the load is indicated in pounds. To get kilograms from them, you need to divide the existing value by 2.2.
When deciphering the size of alloy wheels and subsequent installation, it may not fit the car. This condition is called the X factor. And it is connected with the fact that alloy wheels can be of the most diverse shapes, while fully meeting the declared and necessary sizes. Therefore, in order to avoid buying the wrong model, it should first be installed on the car, at least for a couple of bolts and slightly rotated. If nothing interferes, does not rest, then the drive is ideal for cars.
How to choose a drive?
In addition to technical characteristics, aesthetic properties as well as the manufacturing method can influence the choice.
Appearance is selected based on personal preferences. Someone likes more knitting needles, someone likes fewer petals.
It is also worth knowing that the wheels are divided into two large categories: steel and alloy.
Steel or stamped are made from a sheet of metal, subsequently connected by welding. This approach allows you to significantly reduce the cost of production. In addition, steel discs are easier to repair and rebuild. Although this is required quite rarely, since they have good strength. On the other hand, the stamped approach gives rise to inaccuracy in production, which promises problems with subsequent balancing. Also, a significant weight of steel increases the total mass.
Alloy wheels are lightweight. The process of their production allows you to create a wide variety of forms and designs. They cost a little more, but as a result, aesthetics and practicality take such discs far ahead.
Alloy view also in turn is divided into two categories: cast and forged. The first type has a granular structure, which gives fragility to the product. This is a known issue with alloy wheels. With prolonged use on rough roads, they tend to crack.
The forged disk has a fibrous structure, which gives special plasticity and does not allow the disk to form chips and cracks. Deforming or destroying it is very difficult.
A small decryption example
It is necessary to disassemble the marking on a single product. For example, decrypt drive sizes on Valdai. There is such a designation - 17x6 6x222.25 Et115 Dia160. Here comes the first diameter of the disk in inches. It is followed by the width under which the tires are selected.
Then follows the number of bolts and the diameter on which they are placed. These are 6 and 222.25, respectively. Et115 is a disk crash. In this case, it means that the axis of symmetry is 115 mm inward from the attachment plane. That is, the disk is convex.
Dia160 - diameter of the central hole in millimeters.
Finally
Careful decoding of the size of the wheels when they are selected will allow you to accurately select the necessary parameters and not become a victim of an unreasonable purchase. Knowing about their characteristics will be useful not only to novice motorists, but also more experienced.