Morgan PLUS SIX, Руководство пользователя

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Tyres’ at the front of the handbook for tyre pressures. It is important that the
tyre pressures are adjusted only when the Tyres are cold (when the car has been
standing for a minimum of 3 hours, or driven less than 1 mile). Always replace
the tyre valve dust cap to prevent dirt and moisture getting into the valve, which
could cause leakage.
Replacement Tyres and Tyre Quality Grading
The tyre quality grade can be found on the tyre sidewall, indicating the quality of
performance of the tyre. For example:
TREADWEAR 230 TRACTION AA TEMPERATURE A
Treadwear
The Treadwear grade is a comparative rating based on the wear rate of the tyre
when tested under controlled conditions on a specified government test course.
For example, a tyre graded 150 would wear one and one-half (1
1 /
2
) times as well
on the government course as a tyre graded 100. The relative performance of
tyres depends upon the actual conditions of their use, however, and may depart
significantly from normal due to variations in driving habits, service practices and
differences in road characteristics and climate.
Traction
The traction grades, from highest to lowest, are AA, A, B, and C. Those grades
represent the tyre’s ability to stop on a wet pavement as measured under
controlled conditions on specified government test surfaces of asphalt and
concrete. A tyre marked as grade C may have poor traction performance.
WARNING The traction grade assigned to this tyre is based on straight-
ahead braking traction tests, and does not include acceleration, cornering,
hydroplaning, or peak traction characteristics.
Temperature
The temperature grades are A (the highest), B, and C, representing the tyre’s
resistance to the generation of heat and its ability to dissipate heat when
tested under controlled conditions on a specified indoor laboratory test wheel.
Sustained high temperature can cause the material of the tyre to degenerate
and reduce tyre life, and excessive temperature can lead to sudden tyre failure.
The grade C corresponds to a level of performance, which all passenger car
tyres must meet. Grades B and A represent higher levels of performance on the
laboratory test wheel than the minimum required by law.
WARNING The temperature grade for this tyre is established for a tyre
that is properly inflated and not overloaded. Excessive speed, under inflation,
or excessive loading, either separately or in combination, can cause heat
build-up and possible tyre failure.
The factory-fitted 18” or 19” tyres on the vehicle are developed using high
performance compounds which become brittle at low temperatures and
therefore should not be used in certain conditions. These tyres should be stored
or used only at temperatures at or above 14° F (minus 10° C) to maintain
performance characteristics and avoid damage to the tyre or injury to persons
or property.
TREA
DWEAR
230 T
RACTION AA TEMPERATURE A
TREA
DWEAR
230 T
RACTION AA TEMPERATURE A