Opel Speedster, Operation, Safety, Maintenance Manual

Page: 59 / 194

For safety reasons, tyres should be replaced
when their tread depth has worn down to 2-
3 mm. The legal permissible minimum tread
depth (1.6 mm) has been reached when the
tread has worn down as far as one of the wear
indicators.
Wear indicators are spaced at equal intervals
around the tyre within the tread. Their position
is indicated by markings on the tyre sidewall.
In the event of tyres requiring changing
consult an Authorised Opel Dealer.
58
General information
Note that the danger of aguaplaning is greater
if the tyres are worn.
Never fit used tyres the previous history and
use of which you do not know.
Tyre designations
Meanings:
e.g. 225/45 R17 91V
225 = Tyre width in mm
45 = Aspect ratio in %
(tyre height to tyre width in %)
R = Belt type: Radial
17 = Fiim diameter in inches
91 = Load index
V = Speed rating
Speed code letters:
Up to 160 km/h (100 mph)
Up to 180 km/h (112 mph)
Up to 190 km/h (118 mph)
Up to 210 km/h (130 mph)
Up to 240 km/h (150 mph)
Up to 270 km/h (168 mph)
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Winter tyres
See page 88 for restrictions.
M+S tyres improve safety and should
therefore be fitted on all wheels.
The design of summer tyres means they have
limited qualities for winter driving.
If the maximum permissible speed for the
winter tyres is less than that of the vehicle, a
notice indicating the maximum permissible
speed for the tyres must be affixed within the
driver&#39;s field
of vision =l¢ 1).
1) Varies from country to country on account of
national regulations.