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IndexDataTechnologyRepairsCar careControlsOverview
Hardtop4. Remove both the left and right side
trim panels
5. Remove the tool used for locking the
hardtop, located next to the hardtop
catch on the left side, position the
tool and turn it forward until you hear
an audible click. Do this both on the
left and right side of the hardtop to
release both catches520de112
6. Remove the two oval cover panels
from the front of the hardtop frame,
using a screwdriver, if necessary
7. Position the tool for locking the
hardtop, and turn it outward until you
hear an audible click. Do this both on
the left and right side of the hardtop
frame to release both catches
8. The hardtop's detent mechanism is
now completely disengaged. With
the aid of an assistant, lift the
hardtop up and over the rear of the
vehicle
Do not set the hardtop down
upright, as damage could result.<520de111
9. Place the hardtop on the hardtop
cart as described in the enclosed
assembly instructions.
To avoid possible damage, take
care not to jam the electrical wires
on the left and right sides.<520de162
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Hardtop10. Press the left and right protective
covers onto the hardtop brackets.520de110
InstallingGoes the same way as for taking the
hardtop off, just do it in reverse order.
Attach the protective cloth insert to the
roof brace (arrow) before placing the
convertible top on the hardtop cart.
Whenever the hardtop is in constant
use, the fabric convertible top does not
need to be dismantled, even in winter.
Before storing the fabric convertible top
in the convertible top compartment, it
has to be completely dry to keep any
water or mildew stains from forming.520de165
Two individuals are required for
removal and installation. When
removing and installing the top, always
proceed with utmost caution to avoid
damage to the vehicle's paint and
bodywork or to the hardtop itself.
The hardtop headining fabric must
not contact the hardtop cart.
Otherwise it jams and can lead to
damage.<
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Information for your safetyThe vehicle's factory-approved safety
tires have been specially designed to
provide optimum safety and driving
comfort on your vehicle.
It is not merely the tire's service life, but
also driving comfort and Ð above all else
Ð driving safety that depend on the
condition of the tires and the mainte-
nance of the specified tire pressure.
Incorrect inflation pressure is a
frequent cause of tire damage. It
also significantly influences the road-
holding ability of your BMW. Check tire
inflation pressures regularly (refer to
page 26), at least every two weeks and
before beginning a longer trip. If this is
not done, incorrect tire pressures can
cause driving instability and tire
damage, ultimately resulting in acci-
dents.<
Safety tiresYour BMW Z8 is equipped with safety
tires.
The assembly consists of self-
supporting tires mounted on specially-
designed wheel rims. Special reinforce-
ment elements support the sidewalls in
the event of pressure loss. Although tire
performance is then restricted, the
vehicle can still be driven on the
deflated tire for a limited distance. Your
vehicle is equipped with a Flat Tire
Monitor that signals you in case of a flat
tire.
For further information, refer to
pages 67, 137.
Tire tread Ð tire damageInspect your tires frequently for tread
depth, wear, signs of damage and for
foreign objects lodged in the tread.
Tread depth should not be allowed to
fall below 0.12 in (3 mm), even though
the legally specified minimum tread
depth is only 0.063 in (1.6 mm). At at
tread depth of 0.063 in (1.6 mm), tread
depth indicators (arrow) in the tread-
groove base will indicate that the legally
permissible wear limit has been
reached. Below 0.12 in (3 mm) tread
depth, there is an increased risk of
aquaplaning, even at relatively
moderate speeds and with only small
amounts of water on the road.390de331
Tire inflation pressure Tire condition
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Avoid overloading the vehicle so
that the permitted load on the tires
is not exceeded. Overloading can lead
to overheating and increases the rate at
which damage develops inside the
tires. You could have a blowout as a
result.
Unusual vibrations encountered during
normal vehicle operation can indicate a
flat tire or some other vehicle defect, as
can variations in normal vehicle
response, such as a pronounced
tendency to pull to the left or right.
Should this occur, respond by immedi-
ately reducing your speed. Proceed
carefully to the nearest BMW center or
professional tire center, or have the
vehicle towed in to have it and its tires
inspected.
Tire damage can endanger the lives of
both the vehicle occupants and other
road users.<
To maintain good handling and vehicle
response, use only tires of a single
tread configuration from a single manu-
facturer. BMW tests and approves
wheel and tire combinations. Refer to
page 104.DOT Quality GradesTread wear
Traction AA A B C
Temperature A B C
All passenger vehicle tires
must conform to Federal Safety
Requirements in addition to these
grades.
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 (1g) 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.TractionThe 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
asphalt 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,
aquaplaning, or peak traction charac-
teristics.<
Tire condition Tire replacement
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Tire replacement Tire rotationTemperatureThe 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 condi-
tions on a specified indoor laboratory
test wheel.
Sustained high temperature can cause
the tire material to degenerate and
reduce tire life, and excessive tempera-
ture can lead to sudden flat tire. The
grade C corresponds to a level of
performance which all passenger
vehicle tires must meet under the
Federal Motor Vehicle Safety Standard
No. 109. Grades B and A represent
higher levels of performance on the
laboratory test wheel than 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 separately or
in combination, can cause heat buildup
and possibly a flat tire.<
Uniform Tire Quality GradingQuality grades can be found where
applicable on the tire sidewall between
tread shoulder and maximum section
width. For example:
Tread wear 200 Traction AA
Temperature A
Use only safety tires as there is no
spare tire available if you get a flat
tire.
For further information, refer to
page 137.
factured is indicated by the code on the
sidewall:
DOT ... 3201 indicates that the tire was
manufactured in week 32 of 2001.
Although tires may have a theoretical
service life of up to 10 years, BMW
strongly recommends that you replace
all tires after an absolute maximum of
6 years.
Between the axles
If different tire sizes are mounted
on the front and rear axles (refer to
page 10 4), then the tires may not be
rotated from one axle to the other.<
The tread wear patterns at the front end
differ from those at the rear Ð the actual
patterns will vary according to indi-
vidual driving conditions. In the inter-
ests of safety and maintaining optimal
handling characteristics, tire rotation is
not recommended.
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Wheel and tire combinations The right choice
Use only wheels and tires
approved by BMW for the corre-
sponding vehicle model, as otherwise
the tires may make contact with the
body as the result of tolerances despite
the same nominal size being used,
resulting in serious accidents. If non-
approved wheels and tires are used,
BMW cannot evaluate their suitability,
and therefore cannot be held liable for
driving safety.<
For wheel and tire specifications
approved by BMW, refer to page 104.
The correct wheel and tire combi-
nation affects different systems
that otherwise will not function prop-
erly, e. g. ABS, DSC and Flat Tire
Monitor.
For this reason, use only tires of the
same brand and tread pattern on the
vehicle and, for example, restore the
approved wheel and tire combination
following a flat tire as soon as
possible.<
Codes on tires and wheels The code on tires has the following
meaning.
Codes on radial tires:
The speed rating indicates the
approved maximum speed for the tire.
Summer tires:
S = up to 112 mph (180 km/h)
T = up to 118 mph (190 km/h)
H = up to 130 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)
ZR = over 150 mph (240 km/h)
Winter tires:
Q M+S = up to 100 mph (160 km/h)
T M+S = up to 118 mph (190 km/h)
H M+S = up to 130 mph (210 km/h) For example:
Nominal width
in mm
Aspect ratio in X
Radial tire code
Rim diameter in inches
Load rating
(not on ZR tires)
Speed rating
(before R on ZR tires)
245/45 R
1896W
Codes on light-alloy wheels:
Protect tire valves from dirt by using
screw-on valve stem caps. Dirt in the
valves frequently leads to slow leaks.
Safety tires carry additional designation
codes; these vary according to manu-
facturer:
Bridgestone RFT
Dunlop DSST
Goodyear EMT
Michelin ZPStorageAlways store tires in a cool, dry place,
protecting them against light whenever
possible. Protect the tires against
contact with oil, grease and fuel. For example:
Rim width
in inches
Code letter for
flange type
Symbol for full-drop
center rim
Rim diameter in inches
Hump on the 2 rim shoulders
8 x 18 EH2
J
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IndexDataTechnologyRepairsCar careControlsOverview
Special features of winter tires Snow chains
*
Choosing the right tireFor winter road driving, BMW recom-
mends winter tires (M+S radial belt
tires). Although all-season M+S tires
provide better winter traction than stan-
dard summer tires with H, V, W, Y and
ZR speed ratings, they generally fail to
provide the same levels of performance
as standard snow tires in winter driving.
In the interests of safe tracking and
steering response, install radial tires
made by the same manufacturer and
with the same tread configuration on all
four wheels if you elect to mount winter
tires.
When selecting winter tires,
remember that you should never
mount anything other than safety tires,
as your vehicle is not equipped with a
spare tire.
For further information, refer to
page 137.<
Do not exceed specified
maximum speeds
Never exceed the maximum speed
for which winter tires are rated.
Unprofessional attempts by laymen to
service tires can lead to damage and
accidents.
Have this work performed by skilled
professionals only. Your BMW center
will be glad to assist you with both their
expertise and the proper equipment for
your vehicle.<
Tire condition, tire pressureOnce the tread depth on winter tires is
less than 0.16 in (4 mm), they are no
longer suitable for winter road driving,
and in the interest of safety should be
replaced.
Comply with the specified tire inflation
pressures Ð and be sure to have the
wheel and tire assemblies balanced
every time you change the tires.
The use of narrow-link BMW snow
chains is permissible in pairs only on
the rear wheels with winter tires with
tire size 245/45 R 18 96 H. Comply with
all manufacturer's safety precautions
when mounting the chains. Do not
exceed a speed of 30 mph (50 km/h)
while driving with mounted snow
chains.
Do not activate the Flat Tire
Monitor when driving with snow
chains mounted. Malfunction warnings
and undetected losses in pressure are
a possibility when driving with snow
chains.
For further information, refer to
page 67.<
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Approved wheel and tire specifications Snow chains
*
It is impossible to install snow chains
on 275/40 R 18 99 W summer tires.
Do not activate the Flat Tire
Monitor when driving with snow
chains mounted. Malfunction warnings
and undetected losses in pressure are
a possibility when driving with snow
chains.
For further information, refer to
page 67.< BMW tests certain tire brands for each tire size, classifies them as road-safe and
approves them. Your BMW center can provide further information.
Observe any regulations applicable in the country of use, e. g. requiring entry in
the vehicle documents.
Tire specifications Light-alloy wheel
BMW Z8
Summer tires
Front: 245/45 R 18 96 W 8Jx18EH2
Rear: 275/40 R 18 99 W 9Jx18EH2
Winter tires
245/45 R 18 96 H M+S 8Jx18EH2
The use of rims and wheel bolts
that do not meet the specifica-
tions of the original factory-installed
equipment will affect the safe operation
of your vehicle and may cause an acci-
dent and personal injury.
Never mix tires of different design, such
as steel-belted radials with radial bias-
belted or bias-ply tires, etc. Mixing tire
types will adversely affect roadholding
and can lead to loss of vehicle
control.<