Tire condition, So to tread depth o, Whee ls and tire s – Mini 2011 Cooper Convertible User Manual

Page 126

Whee

ls and tire

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performance which all passenger car tires must
meet under the Federal Motor Vehicle Safety
Standard No. 109. Grades B and A represent lev-
els of performance on the laboratory test wheel
that exceed the minimum required by law.

The temperature grade for this tire is
established for a tire that is properly

inflated and not overloaded. Excessive speed,
underinflation, or excessive loading, either sep-
arately or in combination, can cause heat
buildup and possible tire failure.

RSC - run-flat tires*

You will recognize run-flat tires by a circular
symbol containing the letters RSC on the side of
the tire, page

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M+S

Winter and all-season tires.
These have better winter properties than sum-
mer tires.

Designation for specially reinforced tires.

Tire condition

Inspect your tires regularly for tread wear, signs
of damage and for foreign objects lodged in the
tread. Check the tread depth.

Tread depth

The tread depth should not drop below 1/8 in/
3 mm, although, for example, European legis-
lation only specifies a minimum tread depth of
1/16 in/1.6 mm. At tread depths below 1/8 in/
3 mm there is an increased risk of high-speed
hydroplaning, even when only small amounts of
water are present on the road surface.

Winter tires

When winter tires wear down past a tread depth
of 1/6 in/4 mm, they become perceptibly less
suitable for winter conditions. In the interest of
safety, new tires should be installed.

Minimum tread depth

Wear indicators in the base of the tread groove
are distributed around the tire's circumference;
the letters TWI, for Tread Wear Indicator, on the
tire's sidewalls identify tires that incorporate
these wear indicators. When tire tread is worn
down to the level of the wear indicators, the
remaining tread depth is 1/16 in/1.6 mm.

Tire damage

Due to low-profile tires, please note that wheels,
tires and suspensions parts are more susceptible
to road hazards and consequential damages.
Unusual vibrations encountered during normal
vehicle operation can indicate tire failure or
some other vehicle defect. This can, for exam-
ple, be caused by driving over curbs. The same
applies to any other abnormal road behavior,
such as pulling severely to the right or left.

In these cases, reduce speed immediately
and have wheels and tires thoroughly

checked. To do so, drive carefully to the nearest
MINI dealer or tire shop that works according to
MINI repair procedures with correspondingly
trained personnel. If necessary, have the vehicle
towed there.
Otherwise, tire damage can be extremely dan-
gerous for vehicle occupants and other road
users.