Porsche 928S 1983, Руководство пользователя

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Tyres and tyre care
Steel braced radial-ply tyres are high quality
engineering products. The life of your tyres
depends not only on correct inflation and wheel
alignment but also on your style of driving: Full
throttle acceleration, very high cornering
speeds and hard braking increase tyre wear.
Moreover, tread wear is greater on rough road
surfaces and in very hot weather. Like the en-
gine, tyres need to be run under the correct
operating conditions at all times. If treated pro-
perly they will be a long lasting safety element
on your car. The following points demonstrate
what is necessary. Your tyres will thank you for
regular care.
1 Tyre pressure
It is absolutely essential to keep your tyres
at the right pressure.
The tyre pressures are shown in the "Techni-
cal data" and must always be regarded as
minimum pressures!
Always check pressures when the tyres are
cold. Never let air out of hot tyres!
The maximum air pressure of 36 psi stamped
on the tires only applies to the U.S. classifica-
tion is not to be confused with normal service
pressures. In Europe, the tire can be inflated
to higher pressures.
Check regularly every 14 days.
2 Valve caps
Valve caps protect the valve against dust
and dirt as well as leaks. Always screw the
caps firmly into position and replace missing
ones immediately.
Check every 14 days.
3 Load and speed
Do not overload your car. Never exceed the
specified roof and trailer coupling loads. A
combination of ov low tyre pressu-
res + high speed + high ambient temperatu-
res is extremely dangerous.
4 Winter tyres
Do not exceed the maximum speed limit (e. g.
160 km/h /100 m.p.h. for M + S [Q] radial-ply
tyres).
An appropriate sticker must be affixed in the
driver's field of vision if the tyre's maximum
speed is less than the car's maximum
speed.
5 Tread
The risk of aquaplaning increases as the
tread depth decreases. Appearance of the
wear indicators (webs in tread grooves 1.6
mm high) should be taken as a signal for ear-
ly tyre replacement.
Check regularly, particularly before and after
long journeys.
6 Lateral and radial run-out
Take the precaution of having the tyres ba-
lanced in spring (summer tyres) and before
the start of winter ( M + S tyres). Note that on-
ly the specified weights may be used for ba-
lancing. (Self-adhesive weights must not co-
me into contact with cleaning agents as they
might otherwise drop off.) Uneven tread
wear indicates that the wheel is not running
true. A specialist should be consulted in
such a case.
See also "Wheel alignment".
Uniform tyre wear can be achieved by perio-
dically changing round the wheels (e. g. af-
ter 5000 km/3000 miles or longer). But only
change the wheels at one side from front to
back and vice versa so that the tyres always
run in the same direction.
Balancing and checking should be perfor-
med by a specialist workshop.
7 Tyre damage
Examine tyres at regular intervals for foreign
matter, nicks, cuts, cracks and bulges (side-
walls). In case of tyre damage where it is un-
certain whether there is a break in the ply
with all its consequences or tyre damage
caused by thermal or mechanical overload-
ing due to a loss of pressure or any other
prior damage, we recommended that the ty-
re be replaced for safety reasons.
If one faulty tyre is replaced it should be no-
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