Saab 95 1967, Руководство по обслуживанию

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TI R ES
MAINTENANCE
The working life of a tire depends very much on the care
it receives and the conditions under which it has to work.
Some of the factors affecting tire wear are listed below.
1. Inflation pressure. It is important to maintain the cor-
rect inflation pressure and to adjust the pressure ac-
cording to load. For correct tire pressures, see group 0.
Correct Overinflated Underinflated
TREAD CONTACT WITH ROADWAY
2. Wheel balancing is necessary to avoid vibration and
consequent wear. Wheels must be balanced both stati-
cally and dynamically.
772-1
3. Wheel alignment. Faulty alignment of the wheels can
cause heavy wear on the tires.
4. Speed. Tire mileage diminishes sharply with rising
speed, mainly due to the greater friction heat gener.
ated.
5. Engine power. Powerful engines give rapid accelera-
tion and high speed, which in turn demand powerful
brakes. This contributes to faster wear on the tires.
6. Road surface. Dry roads offering a good grip fOr the
tires cause a great deal of wear.
7. Manner of driving. The temperament of the driver may
weigh more heavily than any other factor. If the accel-
eration and braking resources of the car are regularly
utilized to the limit, this will quickly wear down the
tires.
A statically balanced wheel should be able to come to
rest in any position when suspended and free to rotate.
A dynamically balanced wheel should rotate in a plane
perpendicular to the axis of rotation, Le. it should have
no tendency to skew during rotation.
The balancing operation should not be performed on new
wheels, but only after some 600—900 miles (1 000—1 500
km) motoring; this is to give the tire time to "shake down"
on the rim.
Wheels need rebalancing after long mileage because tire
wear alters the distribution of weight.
NOTE
When a wheel spinner is used, the speedometer read-
ing must not exceed 40 mph (70 km/h).
m
1977