Know Your Rims & Wheels

Just found this information on the web, maybe can give all of us new knowledge about our beloved rims..

Name Of Wheel Parts

civic es rims

Wheel Size

Offset

civic rims offset

The offset indicates the distance from the center of the rim to the attaching disk part (unit:m/m). As seen in the attached drawing, the offset is indicated by “+” when the fitting surface extends beyond the central line of the rim and “-” when it is falls within. Caution is required to prevent the tire from coming into contact with the fender of the vehicle or the brake caliper if the offsets are very different.

PCD

civic rims

The number of bolts used to install a wheel varies from 4 to 6 depending on the vehicle model (except for some vehicle type), thus the wheel to be installed should also possess the same number of hub bolt holes. P.C.D. stands for pitch circle diameter, and indicates the diameter of the circle in mm connecting the center of each hub bolt. Since the P.C.D. also varies according to the vehicle model, make sure a suitable one is selected.

Clearance

Fender clearance indicates the marginal space between the tire and the fender or body of the vehicle. Inner clearance indicates the distance between the tire and wheel and the body part which is positioned closest to the tire and wheel. Dimensions for both right and left clearance should be measured on a level surface, and the smaller value is then considered as the inner clearance.

Tyre Size

1-Tire width (mm or inch)
2-Aspect ratio
3-Radial construction
4-Rim diameter
5-Load index
6-Speed symbol
7-Tire outer diameter (inch)
8-Ply rating

———————————————————-SAFETY STANDARD——————————————————-

Japan Light Alloy Wheel (JWL) Standard for Passenger Cars. The Ministry of Land, Infrastructure, and Transport requires that aluminum wheels for passenger cars (with 3, 5, and 7-number plates) sold in Japan bear the JWL mark. The JWL mark can be displayed on wheels that have passed the standard through a self-certification system.

Similarly, the ministry requires aluminum wheels for trucks and buses (with 1 and 4-number plates) to bear the JWL-T mark. Even if a vehicle is classified as a passenger car (with 3, 5, or 7-number plates), if it comes with LT tires as standard equipment due to its GVW (gross vehicle weight), it must use aluminum wheels bearing the JWL-T mark.

A third-party entity called the Vehicle Inspection Association verifies whether a product meets the requirements prescribed by the JWL or JWL-T standard. This association permits a product to bear a VIA mark if it passes rigorous quality and strength verification tests conducted in accordance with the JWL or JWL-T standard.