Porsche 911 Carrera - Manual (Page 274)

After driving off road, examine tires for signs
of damage such as cuts, tears, bulges or
foreign objects stuck in the tread. Replace a
damaged tire if necessary.
Cross curb edges slowly and at right angles
if possible. Avoid driving over steep or sharp
curbs.
In cases of doubt, have the wheel (particularly
the inner side) checked by an authorized
Porsche dealer.
Tire replacements
If in doubt, contact your Porsche dealer. Use only
tire makes and types approved by Porsche.
If you do not use a Porsche recommended
replacement tire, make sure that you pur-
chase your new tires from a reputable tire
dealer and that the dealer complies with all
manufacturers warnings for those tires.
Only tires with the same make and with the
same specication code (e.g. “N0”, “N1”...)
can be mounted.
Before mounting new tires, check with your
Porsche dealer about the current release
status.
Use tires with “ZR” quality standards. There are
currently no standards concerning tire strength at
speeds above 150 mph (240 km/h).
Tires should be replaced no less than on one axle
at the time. Only tires of the same make and type
must be used. Mixed tires are not permissible.
Initially, new tires do not have their full traction. You
should therefore drive at moderate speeds during
the first 60 - 120 miles (100 - 200 km).
If new tires are installed only on one axle, a
noticeable change in handling occurs due to
the different tread depth of the other tires. This
happens especially if only rear tires are replaced.
However, this condition disappears as the new
tires are broken in.
Please adjust your driving style accordingly.
Installation of new tires should only be done by a
qualified tire technician.
Valves
Rubber valve stems must be replaced every time
a tire is replaced. For metal valves, the installation
and replacement instructions must be observed.
Use only genuine Porsche metal valves.
Protect the valve inserts against soiling with
valve caps. Soiled valve inserts can cause a
gradual loss of air.
Use only plastic valve caps.
Parking at the curb
Warning!
Hard impacts against curbs (or trafc islands)
are dangerous and may cause hidden tire
damage which is not noticeable until later.
Such damage can result in accidents at high
speeds causing serious personal injury or
death. Depending on the force of impact, the
edge of the rim can also be damaged.
If you are in doubt, have the wheel checked by
an expert, particularly if you suspect damage
on the inside.
272
Practical Tips, Emergency Service