Porsche 911 2020 Owner's Manual page 309

G – Term of tubeless or tube tire
Identification for tubeless tires.
Speed code letter
The speed code letter indicates the maximum per-
mitted speed for the tire. This rating is indicated on
the tire side wall.
T
up to 118 mph (190 km/h)
H
up to 131 mph (210 km/h)
V
up to 150 mph (240 km/h)
W
up to 167 mph (270 km/h)
Y
up to 186 mph (300 km/h)
(Y) up to 186 mph (300 km/h) as for Y
tires. Speeds of more than 185 mph
(300 km/h) are also possible at a
maximum tire load capacity of 85%
(confirmation from tire manufacturer
required for speeds of more than
185 mph (300 km/h)).
Reading off inscription on wheels
The information is inscribed on the back of the
spokes near the tire valve.
Fig. 245: Inscription on wheel
A Rim width in inches
B Rim-flange contour code letter
C Symbol for drop-center rim
D Rim diameter in inches
E Double hump
F Rim offset in mm
Identifying tire damage
Hidden tire damage and
WARNING
damage to the rim flange
Hidden tire damage can cause the tire to burst. You
may lose control of the vehicle.
e Check tires, including the sidewalls, regularly for
embedded foreign bodies, nicks, cuts, cracks and
bulges.
e Cross curb edges slowly and at right angles if
possible. Avoid driving over steep or sharp curbs
or objects with sharp edges (such as stones)
heavily or at an acute angle.
e If in doubt, have the tire, especially the inner side,
checked by an expert. Go to a qualified special-
ized repair shop. Porsche recommends an au-
thorized Porsche dealer, as they have trained
technicians and the necessary parts and tools.
e Tire repairs are not permissible under any cir-
cumstances. Sealing a tire with tire sealant is
only an emergency solution so that you can drive
to the nearest workshop.
For safety reasons, tires must be replaced in the
event of the following types of damage:
– If the possibility of a fracture in the ply cannot be
ruled out.
– If the tire was thermally or mechanically over-
loaded as a result of pressure loss or other prior
damage.
Replacing tires and wheels
e Switch off the ignition when changing a wheel.
Lack of grip
WARNING
Initially, new tires do not provide their full grip.
e You should therefore drive at moderate speeds
during the first 125 mls (200 km) to extend the
service life of the tires and achieve full perform-
ance capability.
e Only tires from the same manufacturer and with
the same specification code (e.g. "NA...") may be
mounted on the vehicle.
e Before mounting new tires, inquire about their
Wheels and Tires
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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