METRIC SIZED TYRE
- Size indication
- Load Index
- Speed Symbol
- Tyre Type (Application) - Tube/Tubeless
- Tread Wear Indicator (TWI)
- Rotational Direction Indicator
- M'sian Standard Mark (MS)
READING THE SIZE INDICATION
* This size indications are classified into 2 types. The imperial size which is very common and the metric size which is standardized based on the I.S.O. standared.
Example of Imperial Size Marking
Example of Metric Size Marking
TYRE CONSTRUCTION
| TREAD (RUBBER) | –This is the external rubber covering a tyre. |
| FUNCTIONS |
–It protects the carcass against injuries from external sources. –It is the recepient of the wear and tear of the tyre through abrasion |
| CARCASS | –The layer or layers of tyre cord topped or coated with rubber forming the main structure of the tyre |
| FUNCTIONS |
–To support the load –To form and maintain the shape and rigidity of the tyre simillar to that of the skeleton for the human body |
| BEADWIRE | –A hard drawn steel wire sheathed with rubber and creeled to the required circumference |
| FUNCTIONS | –To ensure a firm and rigid seating of the tyre on the rim |
| TREAD GROOVES | –These are drainlike structures formed on the tread crown region of the tyres |
| FUNCTIONS |
–To evacuate water between the tread contact area and road surface. –To minimise the heat built-up effect on the tread crown region of the tyre |
| RIMLINE | –This is a raised circumferential on the sidewall just above the bead flange level on the tyre. |
| FUNCTIONS | –To determine the correct seating position of the tyre on the rim |
| INNER LINER | –This is a butyl rubber lining that covers the whole of the inner periphery of the tyre in tubeless tyres |
| FUNCTIONS | –It acts as an inner tube to retain inner air pressure in tubeless tyres. |
RIM TERMINOLOGY |
|
|
RIM |
–The outer ring of the wheel. |
|
BEAD FLANGE |
–The raised of the rim. |
|
BEAD SEAT |
–The platform on the rim where the beads of the tyre are seated |
Load Capacity Index
Speed Symbol
