D Car — November 2003

Tire and wheel basics: first, learn the tire’s construction and the names of its parts. You know that almost all tires used on passenger cars today are radial tires, right? The illustration above shows a cross-section of a tubeless radial tire. It is called a radial tire because the reinforcing material inside it, the carcass, is arranged in the radial direction. Some tires have carcass plies layered diagonally in alternating directions; those are called cross-ply tires, but they are hardly used on passenger cars today. Many modern tires also use steel in the belt, making them less likely to puncture when they run over a nail. The diagram below also shows the general construction of a wheel and the names of its parts, so let’s check those too…

10/10/2003

A solid lesson from the basics—even things you feel you cannot ask other people about!

Sport-compact style

Sport-compact Academy

Lesson 2

Tires play an important role in any car, not just a sport compact. No matter how powerful the engine is, the car cannot go anywhere without tires. So, let’s learn the basics of tires and wheels…

Lesson 1: Learn the names of the tire parts

Names of the tire parts

First, get a firm grasp of the basics of tires and wheels.

Sidewall

Carcass

Bead wire

Cross-section of a tubeless radial tire. A radial tire has a flexible sidewall construction.

…and learn them.

Learn the names of the tire parts

and their names

Wheel parts

Spot weld

Rim width; rim centerline

Rim diameter

(bolt-hole pattern circle diameter…)

Hub-hole diameter

← Wheel construction and names of its parts. The illustration shows a steel wheel, but the names of the parts are the same for aluminum-alloy and other lightweight-alloy wheels.

Flange (lip)

Tire bead seat

D Car — November 2003

About this issue

Page 90 — English draft translation