19.2. Indicators of deterioration of tyres
Fig. 13–1. Marks arrangement on sidewallsе tyres (for example, letters TWI or the pictogramme in the form of a triangle)
In flutes of drawing of a protector of tyres there are indicators of deterioration of tyres in height of 1,6 mm located at right angle to a direction of progress of the tyre. Indicators (from six to eight depending on firm-manufacturer) are placed through equal distances on a tyre circle. Marks on sidewallsе tyres (for example, letters TWI or the pictogramme in the form of a triangle) show a site of indicators of deterioration of tyres (fig. 13–1).
Intensive deterioration of tyres is promoted by a sports manner of driving, sharp dispersals and braking.
Tyres it is possible to maintain of 1,6 mm before achievement of height of a protector, that is depth of flutes of a protector on all surface of the tyre should be not less than 1,6 mm. However with a view of safety it is recommended to change tyres at depth of a protector of 2 mm.
Tyres "M+S" on snow have sufficient coupling with road at height of a protector not less than 4 mm.
It is necessary to examine the tyre. If deep cuts reach a cord, the steel cord will be корродировать from a getting moisture.
The worn out tyres do not provide, necessary coupling with a road covering, especially at movement with high speed on wet road. Besides, at the worn out tyres there comes hydroplaning (loss of coupling with a wet road covering) much faster.