BMW i4 GRAN COUPE 2022, Руководство пользователя

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Uniform Tire Quality Grading
Quality grades can be found where applicable
on the tire sidewall between tread shoulder
and maximum section width.
E.g.: Treadwear 200; Traction AA; Tempera-
ture A
DOT Quality Grades
Treadwear
Traction AA A B C
Temperature A B C
All passenger vehicle tires must conform to
Federal Safety Requirements in addition to
these grades.
Treadwear
The treadwear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified gov-
ernment test course. E.g., 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 conditions of their use, how-
ever, and may depart significantly from the
norm due to variations in driving habits, service
practices and differences in road characteris-
tics 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 specified government
test surfaces of asphalt and concrete. A tire
marked C may have poor traction perform-
ance.
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 characteristics.
Temperature
The temperature grades are A, the highest, B,
and C, representing the tire's resistance to the
generation of heat and its ability to dissipate
heat when tested under controlled conditions
on a specified indoor laboratory test wheel.
Sustained high temperature can cause the
material of the tire to degenerate and reduce
tire life, and excessive temperature can lead to
sudden tire failure. The grade C corresponds to
a level of performance which all passenger car
tires must meet under the Federal Motor Vehi-
cle Safety Standard No. 109. Grades Band A
represent higher levels of performance on the
laboratory test wheel than the minimum re-
quired by law.
Warning
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, underinfla-
tion, or excessive loading, either separately
or in combination, can cause heat buildup
and possible tire failure.
Runflat tires
Runflat tires, refer to page 303 , are labeled
with a circular icon containing the letters RSC
marked on the tire sidewall.
M+S
Winter and all-season tires with better cold
weather performance than summer tires.
Tire tread
Summer tires
Do not drive with a tire tread depth of less than
0.12 in/3 mm, otherwise there is an increased
risk of aquaplaning.
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Wheels and tires MOBILITY
299
Online Edition for Part no. 01405A546C7 - II/22