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Tire Unit Indication ▶
Tire Inflation Pressure (32 psi) ▶
Proper inflation
pressureExcessive inflation pressure Low inflation
pressure
Aspect ratio (%)
= Nominal section height (H) / Nominal section
width (W)
X 100
The contact area between the
ground and tire faces the tread
layer completely. Thus the
driving force and the braking
force are optimized, and the tire
is worn out evenly resulting in
increased life.The contact area between the
ground and tire is not enough,
so the tire is worn out unevenly
and the tire is vulnerability to
outside influence.The contact area between the
ground and tire is excessive, so
a lot of heat is generated and
the tire is worn out unevenly
and abnormally.
Tread width Tread width Tread width
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14-154170-09
During driving, the rotating tire repeats deformation and restoring movement in is tread. This happens
when the tire pressure is low in high speed driving.
However, when the wheel rotating speed is fast, the tire is deformed even before it is restored to its
original shape and the trembling wave appears on the tread portion. If this symptom lasts for an
extended period of time, the tire can be blown out in a short period of time.
If the standing wave symptom occurs on the tire, rubber on the tread comes off and eventually the tire
can be blown out which is very dangerous. When driving at high speed, the inflation pressure should be
increased to decrease heat generation due to extension and contraction motion, to decrease
hydroplaning and to prevent standing wave.
To prevent this symptom, it is recommended to increase the tire pressure 10 ~ 30 % higher than the
specified pressure value in high speed driving.
Specified tire inflation pressure32psi
2. ABNORMAL TIRE SYMPTOM
Standing Wave ▶
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When the vehicle is driven on a road surface covered with water at high speed, tires do not contact with
the road surface but rotate floating on a thin film of water.
It causes brake failure, lower traction force and losing the steering performance.
To prevent this, increase the tire inflation pressure, use tires with leaf shape tread which is not worn.
However, it is a best measure to drive slowly. Hydro Planing ▶
Vehicle speed ≤ 60 km/h
No Hydro planningVehicle speed = 80 km/h
Partial Hydro planningVehicle speed ≥ 100 km/h
Full Hydro planing
