What are some little-known facts about rims that you don't know?
May 22, 2025
What are the characteristics of different rims?
Nowadays, the two types of rims we commonly see in the market are steel rims and aluminum alloy rims. Aluminum alloy rims are not only light in weight but also come in a variety of styles and have beautiful designs. They are mostly used in some mid-to-high-end models. Although steel rims are relatively heavy and not good-looking in style, they are simple and sturdy, and have a low manufacturing cost. They are very common in some low-end models or pickup trucks and minivans.
Steel rims have the characteristics of simplicity and sturdiness, and are also commonly seen in some American police cars.
The size and parameters of the rim
The parameters of the wheel rims are closely related to the selection of tires. When choosing tires, it is necessary to first understand the size and parameters of the vehicle's wheel rims, which are mainly determined by parameters such as wheel diameter, wheel width, wheel offset, center hole size, and hole spacing.
Most of the information about the wheel rim is printed on the inner side.
The size of rims is generally measured in inches (in). When we often say "15 inches" or "16 inches rims", we are referring to the diameter of the rims.
The size of the rim that is matched can also be seen from the information on the tire.
The rim width, commonly known as the J value, refers to the distance between the flanges on both sides of the rim. The width of the rim determines the width of the tires that can be installed. For rims of the same size, if the J values are different, the aspect ratio and width of the tires to be selected will also be different.
The width of the rim determines the width of the tires that can be installed.
Rim offset (ET) refers to the distance from the centerline of the rim to the mounting surface, with the unit being millimeters (mm). The smaller the offset, the more the rims will be out of the vehicle after installation. If the offset is too large, the rims will rub against the vehicle's suspension system.
If the wheel rim offset is too small, the wheel rim will deviate much from the vehicle after installation.
For wide-body modifications like this one, the rim offset (ET value) is relatively small, or even negative.
The size of the center hole of the wheel rim determines whether the wheel rim is installed firmly. If the center hole of the wheel rim is too large, a ring needs to be added to the shaft head of the car bearing during installation to ensure the wheel rim is installed stably. If the center hole is too small, the rim cannot be installed at all.
The center hole of the wheel rim must not be smaller than the shaft head of the car bearing; otherwise, it cannot be installed.
The rim hole spacing (PCD), literally understood, is the distance between the fixed bolts at the center of the rim. In fact, it is to connect the center points of the fixed bolts into a circle, and the number of bolts multiplied by the diameter of the circle is the hole spacing. For example, if the hole spacing of this wheel rim is 5×112mm, it means that the PCD of this wheel rim is 112mm and there are 5 bolts in the hole positions.
The distance between the rim holes determines whether it can be installed.
Classification of rims
Nowadays, the shapes and styles of rims on the market are extremely diverse. Classified by the spokes, they can be divided into five-spoke, six-spoke, double five-spoke, multi-spoke, V-shaped, and layered rims, etc. Classified by processing techniques, they can be categorized as baking varnish, electroplating, and metal wire drawing etc.
