Operation Manual

228 Driving and operation
Picture no: 17216t.tif
The legally permissible minimum tread
depth (1.6 mm) has been reached when
the tread has worn down as far as one of
the wear indicators (TWI
1)
). A number of
wear indicators are spaced at equal
intervals around the tyre within the tread.
Their position is indicated by markings on
the tyre sidewall.
General information
z The danger of aquaplaning is greater if
the tyres are worn.
z Tyres age, even if they are used only very
little or not at all. A spare wheel which
has not been used for six years should be
used only in emergencies; drive slowly
when using such tyres.
z Never fit used tyres the previous history
and use of which you do not know.
z So as not to impair brake cooling, use
only wheel trims approved for use on
your vehicle.
Tyre designations
Meanings:
e.g. 195/65 R 15 91 H
Speed code letters:
1)
TW I = Tread Wear Indicator.
195 =Tyre width inmm
65 = Cross-section ratio
(tyre depth to width) in %
R = Belt type Radial
RF = Type: Run-flat
15 = Wheel diameter in inch
91 =Load index
e.g. 91 corresponds to 618kg
H = Speed code letter:
Q up to 100 mph (160 km/h)
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 168 mph (270 km/h)