2000 BMW Z8 Owners Manual

96n
Information for your safetyFactory-approved steel-belted radials
with emergency driving characteristics
are meant for your vehicle, offering
optimum driving safety as well as the
driving comfort you desire.
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 con-
dition of the tires and the maintenance
of the specified tire pressure.
Incorrect inflation pressure is a frequent
cause of tire damage. It also signifi-
cantly influences the roadholding ability
of your BMW.
Check tire inflation pressures reg-
ularly (refer to page 24), at least
every two weeks and before beginning
a longer trip. If this is not done, incor-
rect tire pressures can cause driving
instability and tire damage, ultimately
resulting in accidents.<
Safety tiresYour BMW Z8 roadster is equipped
with safety tires.
The safety tires are made of self-sup-
porting tires and customized wheel
rims. Reinforcing the tires makes sure
that they remain upright and still drive-
able to a limited degree even in the
event of loss of pressure. Your vehicle
is equipped with a tire pressure monitor
that signals you in case of a flat tire.
For further information, refer to
pages 65, 135.
Tire inflation pressure

97n
IndexDataTechnologyRepairsCar careControlsOverview
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 a
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 moder-
ate speeds and with only small amounts
of water on the road.390de331
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
tire failure or some other vehicle defect,
as can variations in normal vehicle
response, such as a pronounced ten-
dency to pull to the left or right. Should
this occur, respond by immediately re-
ducing 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.<
Tire condition

98n
Tire replacement 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 103.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 (1 1/2) 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 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.<
TemperatureThe 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 re-
duce tire life, and excessive tempera-
ture can lead to sudden tire failure. The
Grade C corresponds to a level of per-
formance which all passenger vehicle
tires must meet under the Federal Mo-
tor 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 possible tire failure.<

99n
IndexDataTechnologyRepairsCar careControlsOverview
Tire replacement 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 tires with emergency
driving characteristics as there is
no spare tire available if you get a flat.
For further information, refer to
page 135.<
Tire ageThe date on which the tire was manu-
factured is indicated by the code on the
sidewall:
DOT ... 1200 indicates that the tire was
manufactured in week 12 of 2000.
BMW recommends the replacement of
all tires when the tires are no more than
6 years old, even if a tire life of 10 years
is possible.

100n
Tire rotation Between the axles
If different tire sizes are mounted
on the front and rear axles (refer to
page 103), 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 individ-
ual driving conditions. In the interests of
safety and maintaining optimal handling
characteristics, tire rotation is not rec-
ommended.
If a proposed interaxle rotation of tires is
based on economic considerations, one
should consider whether the costs for
the rotation are likely to be recouped by
any increase in the service life of the
tires that might be realized. Rotation
should always be carried out at short in-
tervals, with a maximum of 3,000 miles
(5,000 km). Consult your BMW center
for more information.
Should you decide to rotate the tires, it
is essential to comply with the following:
Rotate tires on the same side only,
since braking characteristics and road
hugging ability could otherwise be
adversely affected.
After rotating the tires, carefully check
and adjust the tire pressure, and reacti-
vate the RDW.

101n
IndexDataTechnologyRepairsCar careControlsOverview
Wheel and tire combinations The right choice Use only BMW-approved tires with
emergency driving characteristics.
Refer to page 103.
Due to the maximum speeds this vehi-
cle can reach, the use of specific brands
and sizes is mandatory. Consult any
BMW center for details. Comply with
local/national regulations.
The correct wheel/tire combinaton
affects different sytems, such as
ABS, ATC, DSC and RDW. The function
of these systems is impaired if improper
wheel/tire combinations are used.
For this reason, use only tires made by
the same manufacturer that have the
same tread configuration and possess
emergency driving characteristics. And
after a flat tire, for instance, restore the
approved wheel-tire combination as
soon as possible.<
Codes on tires and wheels The tire codes will aid you in selecting
the correct tire.
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) 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 18 96 W
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)
Codes stamped 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.
Tires with emergency driving character-
istics also possess an additional identi-
fication mark that varies by manufac-
turer, e. g.:
Bridgestone RFT
Dunlop DSST
Goodyear EMT
Michelin ZP 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 H 2
J

102n
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 and ZR
speed ratings, they generally fail to pro-
vide 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.
Mount only winter tires that have been
approved by BMW. Any BMW center
will be glad to provide you with informa-
tion on the best winter tires for your
particular driving conditions.
Use only winter tires with emer-
gency driving characteristics as
there is no spare tire available if you get
a flat.
For further information, refer to
page 135.<
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.StorageAlways store tires in a cool, dry place.
Store them away from light whenever
possible. Protect the tires against con-
tact with oil, grease and fuel.
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 activate the RDW system
while using snow chains.
Malfunction warnings and undetected
losses in pressure are possible when
driving with snow chains.
For further information, refer to
page 65.<

103n
IndexDataTechnologyRepairsCar careControlsOverview
Approved wheel and tire specifications Comply with the specifications for tires
and wheels in the vehicle's documents.
If sizes not approved by the manufac-
turer are mounted, an entry in the vehi-
cle's documents may be necessary. Tire specifications Light-alloy wheel
BMW Z8
Summer tires
Front: 245/45 R 18 96 W 8Jx18 EH2
Rear: 275/40 R 18 99 W 9Jx18 EH2
Winter tires
245/45 R 18 96 H M+S 8Jx18 EH2
Snow chains
*
It is impossible to install snow chains
when using summer tires 275/40 R 18
99 W.
Do not activate the RDW system
while using snow chains.
Malfunction warnings and undetected
losses in pressure are possible when
driving with snow chains.
For further information, refer to
page 65.<
The use of rims and wheel bolts
that do not meet the specifications
of the original factory-installed equip-
ment will affect the safe operation of
your vehicle and may cause an accident
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.<