Who Invented The First Tire?
It was invented in
1888, by John
This would be the
end of the solid tire.
The tyre acts as the primary suspension,
cushioning the vehicle from the effects of a
It also provides frictional contact with the road
This allows the driving wheels to move the
The front tyres allows the wheels to steer .
The tyres allow the brakes to slow or stop the
Components that go
into a tire.
What percent of a tire is
By weight, give or
By volume, quite a
Why are Tires Black?
To protect the rubber
from the harmful UV
A common type of
UV stabilizer called a
is added to capture
and absorb these
harmful UV light
•Beads two rings that are made of steel wire
and encased in rubber.
They hold tire side walls snugly against the
•Body Plies rubberized fabric and cords
wrapped around beads.
Form carcass or body of the tire.
•Tread outer surface of the tire that contacts the road.
•Sidewall outer part of the tire that extends
the bead to the tread. Marking on the sidewall
provides the information about the tire.
•Liner thin layer of rubber that is bonded to
the inside of the plies. It provides a leak proof
membrane for tubeless tires.
•Belts used to strengthen the body plies and
and stiffen the tread. They lay between the
tread and plies.
Wheel & Rim
Some vehicles are fitted with alloy wheels that are
made of magnesium or aluminium.
Steel Wheels – A very popular design of wheel.
Very strong and cheap to produce.
Alloy Wheels – Attractive and light weight, but can
be difficult to clean.
Spoked Wheels – Used on older sports vehicles,
but cannot be fitted with tubeless tyres.
Divided rims – the rims are made in two halves
which are bolted together, the rims must never
be separated while the tyre is inflated.
Split rims – the tyre is held in place by a large
circlip, do not remove the tyre unless you have
been properly trained
Three functions – It retains the air, it
allows inflation and deflation.
The rubber stem of the valve is
pulled into the wheel.
The valve core contains a
spring loaded air valve insert.
The valve core also has a sealing
washer and a seat washer.
The valve cap keeps out
dust and helps keep air in.
Valve stemValve core
Tyre pressures must only be checked and
adjusted when the tyre is cold
Bias Ply Tires
•The plies run at an angle from
bead to bead.
•One of the oldest design.
•Does not use any belts.
•Allows body of the tire to flex easily.
•Improved cushioning, hence smooth ride on rough roads.
•Weakness of Bias-plies is that it reduces traction at high
speeds and increase rolling resistance.
Belted Bias Tire
•Bias ply tires with belts added to
increase tread stiffness.
•Belts and plies run at different angles.
•Belts do not run around the sidewalls,
they lay under the tread area only.
•Provides smooth ride and good traction.
•Offers some reduction in rolling resistance over a bias ply tire.
Radial Ply Tire
•Plies running straight across from
bead to bead, with stabilizer belts
directly beneath the tread.
•Has a very flexible sidewall and a
stiff tread, giving it a very stable footprint.
•Disadvantage is that it may produce a
harder, or harsher, ride at low speeds.
P 205/55 V R 16
P - PASSENGER
T - TEMPORARY
LT - LIGHT TRUCK
C - COMMERCIAL
55, 60, 65 70 ETC
B - BIAS-BELTED
D - DIAGONAL BIAS
R - RADIAL
(INCHES) 13, 14 ETC
P 205/55 V R 16P 205/55 V R 16P 205/55 V R 16P 205/55 V R 16P 205/55 V R 16P 205/55 V R 16P 205/55 V R 16
B (31 MPH) -
V (150 MPH) -
Z (OVER 150 MPH)
Tire pressure should be check monthly
Tire pressure should be checked cold
For every 10° Fahrenheit change in air temperature,
your tire's inflation pressure will change by about 1
The air pressure in the tire supports the car, make
sure that it is the right amount.
If you check the air pressure inside the shop at a
temperature of 70° will the tires be the right pressure
when it goes outside at 0°?
Nitrogen in tires
Nitrogen is a dry inert gas. That means
Nitrogen leaks out of the sidewall three times
slower then oxygen.
Oxygen oxidizes the rubber in the sidewall.
Plus the moisture in the air will rust the steel
This is the Maximum pressure for the tire not
the normal pressure, use only if car is fully
EFFECTS OF TIRE
Wide tires that are under inflated can also wear in the center
Tires are specified by the manufacture with a maximum load
rating. Loads exceeding the rating can result in unsafe condition
that can lead to steering instability and even rupture
Code mph km/h Code mph km/h
A1 3 5 L 75 120
A2 6 10 M 81 130
A3 9 15 N 87 140
A4 12 20 P 94 150
A5 16 25 Q 100 160
A6 19 30 R 106 170
A7 22 35 S 112 180
A8 25 40 T 118 190
B 31 50 U 124 200
C 37 60 H 130 210
D 40 65 V 149 240
E 43 70 Z over 149 over 240
F 50 80 W 168 270
G 56 90 (W) over 168 over 270
J 62 100 Y 186 300
K 68 110 (Y) over 186 over 300
The speed rating denotes the maximum speed at which a tire is
designed to be operated. For passenger vehicles these ratings range
from 99 to 186 miles per hour (159 to 299 km/h).
EFFECTS OF SPEED ON A
Tires are tested under Laboratory conditions they are not
worn out, are properly inflated, not over loaded, damaged
Just because the tire is rated at these speeds does not
mean the car is safe or legal to drive at those speeds.
Tyres are Safety Critical components, which
require simple but regular care and attention.
Tyres in good condition will hold your vehicle
securely on the road, allowing it to stop, start and
manoeuvre safely --worn out, under-inflated or
unsuitable tyres will not.
They are your only contact or “footprint” with
the road. A tyre with a big footprint will provide
better grip on dry roads
READ YOUR TYRE
Tyre Age :Tyres carry a three digit age
code on the sidewall indicating the
month and year of manufacture. For
example 120 means the tyre was
manufactured in December 2000. Some
other manufacturers codes give the
week number of manufacture and Year:
1700 17th week of year 2000.
There is also a code in mixed letters and
numbers denoting the factory location.
T or TL+: Tyre is Tubeless Do not fit
tubes into tubeless tyres
Csm15 Jun 03
15 Tonnes Overload on 25T
capacity trailer .
DO NOT OVERLOAD TYRES!
Tyres have kg or lbs
load ratings marked -
giving maximum loading
per tyre. Do NOT
FAST and HOT = OVERHEATING
Csm15 Jun 03
High speed journey from Muscat
over 120kph non stop -past Nizwa,
front tyre blew.
Rollover No seatbelts being worn