Porsche 911 Manual page 243

gauge and reduce tyre pressure or add more air if
necessary. Check the inflation pressure again.
4. Switch off compressor.
5. Unscrew the compressor's filler hose.
Information
The tyre pressure can also be checked at a service
station and the tyres can be inflated.
Reducing inflation pressure
1. Switch off compressor.
2. Open air bleed screw on the filler hose until the
correct inflation pressure is achieved.
Reading off inscription on tyres
Fig. 215: Inscription on tyres
A Nominal width in mm
B Cross-section ratio in %
C Belt type code letter
D Rim diameter in inches
E Load rating code number
F Speed code letter
The speed code letter F indicates the maximum
permitted speed for the tyre.
H
up to 210 km/h (130 mph)
V up to 240 km/h (150 mph)
W
up to 270 km/h (168 mph)
Tyres and Wheels
Y
up to 300 km/h (186 mph)
(Y) up to 300 km/h (186 mph) as for Y
tyres. Speeds of more than 300 km/h
(186 mph) are also possible at a max-
imum tyre load capacity of 85 % (con-
firmation from tyre manufacturer
required for speeds of more than
300 km/h (186 mph)).
Detecting tyre damage
Hidden tyre damage and
WARNING
rim flange damage
Hidden tyre damage can cause the tyre to burst. You
may lose control of the vehicle.
e Check tyres, including the sidewalls, regularly for
foreign bodies, nicks, cuts, cracks and bulges.
e Cross kerb edges slowly and at right angles if
possible. Avoid heavy or sharp-angled impact
against steep and sharp kerbs or sharp-edged
objects (e.g. stones).
e If in doubt, have the wheel – particularly the in-
ner side – checked by an expert. Visit a qualified
specialist workshop. Porsche recommends a
Porsche partner as they have trained workshop
personnel and the necessary parts and tools.
e Tyres must never be repaired under any circum-
stances. Sealing the tyre with the tyre sealant is
only an emergency solution to enable you to
drive to the nearest workshop.
In the case of the following tyre damage, the tyre
must be replaced for safety reasons:
– Tyre damage where the possibility of a ply frac-
ture cannot be ruled out.
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
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