BMW Z3 COUPE, Руководство пользователя

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Index
Data
Te
chnolog
y
Repairs
Car care
Controls
Overview
Tire condition Tire replacement
Never continue driving on a de-
flated (flat) tire. A flat tire greatly
impairs steering and braking response,
and can lead to complete loss of con-
trol over the vehicle.
Avoid overloading the vehicle so that
the permitted load on the tires is not
exceeded. This can lead to overheating
and increases the rate at which damage
develops inside the tires. The ultimate
result can assume the form of a sudden
air loss.
Unusual vibrations encountered during
normal vehicle operation can indicate
tire failure or some other vehicle defect,
as can variations in normal vehicle re-
sponse, such as a pronounced ten-
dency to pull to the left or right. Should
this occur, respond by reducing your
speed immediately. Drive carefully to
the nearest BMW center or professional
tire dealer, or have the vehicle towed in
to have it and its tires inspected.
Tire damage (up to and including sud-
den and complete air loss) can pose an
extreme hazard for both vehicle occu-
pants and other road users.
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To maintain good handling and vehicle
response, use only tires of a single tread
configuration from a single manufac-
turer. BMW tests and approves wheel-
tire combinations. Refer to page
116 .
DOT Quality Grades
Tread wear
Traction AA A B C
Temperature A B C
All passenger car tires must con-
form to Federal Safety Require-
ments in addition to these grades.
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Tread wear
The tread wear grade is a comparative
rating based on the wear rate of the tire
when tested under controlled condi-
tions on a specified government test
course.
For example, a tire graded 150 would
wear one and one-half (1-
g
) times as
well on the government course as a tire
graded 100. The relative performance
of tires depends upon the actual condi-
tions of their use, however, and may
depart significantly from the norm due
to variations in driving habits, service
practices and differences in road char-
acteristics and climate.
Traction
The traction grades, from highest to
lowest, are AA, A, B and C.
Those grades represent the tire's ability
to stop on wet pavement as measured
under controlled conditions on speci-
fied government test surfaces of as-
phalt and concrete. A tire marked C
may have poor traction performance.
The traction grade assigned to
this tire is based on straight-
ahead braking traction tests, and does
not include acceleration, cornering,
hydroplaning, or peak traction charac-
teristics.
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