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| How to use tires: |
1. |
Tires must be fitted on special vehicles and
rims. |
| 2. |
On an axle should fit tires of the same size, brand, dimension,
ply-rate, inflation pressure and tread pattern. |
| 3. |
When fitting new tires on a vehicle we recommend to replace
all the old tires with new ones or to put new tires on front
axle and outside of the back axle. |
| 4. |
When back axle uses dual tires the dual spacing should not
be less than 20mm and not more than 35mm and the opening on
the wheels should be in alignment. |
| 5. |
When fitting tires which have special running directions,
the running direction should be the same with the running direction
of wheel. When these kind of tires often run on hard road, the
tires on the front wheels can be fitted in opposite direction
in order to reduce rolling resistance and save fuel. |
| 6. |
Tires fitted on a vehicle must keep inflated. If you will
not operate a vehicle for more than one week please leave it
in garage or a shady place avoiding sunbeam shining directly
upon it and jack it up to prevent crack of tire surface. |
| 7. |
Tires should be inflated according to specified pressure.
But when vehicles run on the roads which have arch of more than
4%, tires on front wheel and inside of the back wheel can be
inflated0.2-0.35kgf/cm2 less than specified pressure. |
| 8. |
When vehicles run for long distance, tire inflating pressure
should often be checked, especially in summer, when you find
pressure 1kgf/cm2 more than specified pressure, you must stop
vehicle at a shady place. After pressure drop to proper value,
start again. |
| 9. |
“More inflation in winter”, “less inflation in summer”, “deflation
midway” can never be used. |
| 10. |
Tires’ load, which should be calculated according to maximum
load of single tire, cannot be exceeded. Goods on vehicle should
be placed evenly. |
| 11. |
According to test reports tires on front wheel wear 20-30%
less than those on back wheel. In order to service life of tires
we recommend to do end to end “X” rotation as regulated when
running 8000-10000km, and at the same time to check tires, inner
tubes and flaps. |
How to read a tyre:
On the sidewall of a tyre you will find various codes and
markings. The list below aims to simplify those codes and
allow you to understand the information imprinted on the
sidewall.
Tyre sizes are made up of a number of different numbers
and letters. For example the tyre size 255/55R 16 85 V is
made up of the following information.
225 This is the tyre width in millimeters.
55 The aspect ratio as a % (the height of the sidewall divided
by the tyre's width).
R Denotes the tyre's construction type - in this case it's
a radial.
16 This is the rim diameter in inches.
85 This is the load rating of the tyre.
V This is the speed rating of the tyre.
Tyre Age - Tyres carry a three digit age code on the sidewall
indicating the month and year of manufacture. For example
129 means the tyre was manufactured in December 1999. Tyres
6 yrs or older need to be changed due to the deterioration
of the tyre.
OTHER MARKINGS
M&S - Identifies Mud and Snow tyres.
DOT Codes - The requirements of the US Department of Transportation
contain a mixture of letters and numbers such as DOT DVDE
MTA 129.
E-Marks - Tyres sold in the European Community must carry
an E -Mark in accordance with ECE Reg 30 - E.g. E4 027550.
ASPECT RATIOS
The Aspect ratio is the ratio of a tyre's width to it's
height. So a 55 series tyre is a tyre whose height is equal
to 55% of its width.
LOAD INDEX
Kg |
Li |
Kg |
Li |
Kg |
Li |
65 |
290 |
85 |
515 |
105 |
925 |
66 |
300 |
86 |
530 |
106 |
950 |
67 |
307 |
87 |
545 |
107 |
975 |
68 |
315 |
88 |
560 |
108 |
1000 |
69 |
325 |
89 |
580 |
109 |
1030 |
70 |
335 |
90 |
600 |
110 |
1060 |
71 |
345 |
91 |
615 |
111 |
1090 |
72 |
355 |
92 |
630 |
112 |
1120 |
73 |
365 |
93 |
650 |
113 |
1150 |
74 |
375 |
94 |
670 |
114 |
1180 |
75 |
387 |
95 |
690 |
115 |
1215 |
76 |
400 |
96 |
710 |
116 |
1250 |
77 |
412 |
97 |
730 |
117 |
1285 |
78 |
425 |
98 |
750 |
118 |
1320 |
79 |
437 |
99 |
775 |
119 |
1360 |
80 |
450 |
100 |
800 |
|
|
81 |
462 |
101 |
825 |
|
|
82 |
475 |
102 |
850 |
|
|
83 |
487 |
103 |
875 |
|
|
84 |
500 |
104 |
900 |
|
|
The load-index figure imprinted on the sidewall of the tyre,
normally just before the speed rating letter, denotes the
maximum load capacity of a tyre when driven at maximum speed.
A list of load indices and maximum weights is give above.
SPEED RATINGS
Speed symbol |
Max speed (km/h) |
Max speed (mph) |
N |
140 |
87 |
P |
150 |
93 |
Q |
160 |
99 |
|
R |
170 |
106 |
S |
180 |
112 |
T |
190 |
118 |
H |
210 |
130 |
V |
240 |
149 |
W |
270 |
168 |
Y |
300 |
186 |
ZR |
240 |
149 |
All tyres carry a speed symbol in the form of a letter indicating
the maximum speed for which the tyre is intended. The table
below shows which speed goes with each letter.
UP STEPPING
Up Stepping to High Performance
Maximizing your car's performance by selecting a lower profile
tyre/larger size rim combination is referred to as "up-stepping."
Plus-one or plus-two tells you how much larger the rim size
is. This "up-step" approach to improving performance
came into being because, although it is possible to get
higher performance without changing rims, it is often necessary
to increase tyre width to the point that steering geometry
is affected, with the result that a change in driving style
or habits becomes necessary.
So in order to fully maximise your vehicle's performance
(which includes preserving the steering geometry) the "up-step"
approach is highly recommended.
ROTATION
Tyre wear rates differ depending on the axle on which the
tyres are fitted and whether the vehicle is front, rear
or four wheel drive. To extend the life of your tyres it
is advisable to change tyre positions on a regular basis.
Different tyre manufacturers may recommend different rotation
periods, ranging from 4-10,000Km. It is advisable to switch
tyres from left to right periodically as well as from the
back to the front of the vehicle.
Certain high performance tyres are position specific and
should not be rotated.
TREAD DEPTH
Current tread depth legislation requires that car tyres
must have a minimum of 1.6mm of tread in a continuous band
throughout the central ? of the tread width and over the
whole circumference of the tyre. To help drivers recognise
when their tyres are nearing the legal limit, tyres are
manufactured with tread wear indicators in the grooves.
However, it is universally recognised in the tyre
industry that the legal limit is wholly insufficient to
protect drivers in adverse driving conditions. Drivers are
therefore recommended to consider replacing their tyres
when the tread depth reaches 3mm.
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