Tires and Temperature!! very useful

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There is a tire for every application from off-road driving to all-out racing, but we’re going to keep it simple and stay with everyday street tires, of which there are three basic types -
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All-Season Tires - Use all-season tires only when your seasons are similar and are mild. All-season tires are a compromise between a good performance tire and a good winter tire. Some All-Season tires are marked M+S – affectionately known as Mud and Snow. All-Season tires should not be used in winter conditions - they have limited traction.
Performance Tires - Sometimes referred to as summer tires, these tires should only be used in warm to hot seasons. The compound of these tires gets very hard as the temperature dips to below 10 degrees Celsius (50 degrees Fahrenheit) and as a consequence they lose their grip.
Winter Tires - There is a lot of confused regarding winter and snow tires. Winter tires should be used in cold conditions when temperatures start to fall below the freezing point. The purpose of a winter tire is to remain pliable and therefore maintain grip - even on ice - during these cold temperatures. Winter tires should not be used in warm temperatures as they will wear out quickly and could possibly shred at high speed! A true snow tire has a large tread pattern with which to notch into the snow. These large and wide treads also help prevent the snow from packing into the tread groves which would thus rendering them ineffective.
The grip that each of these types of tire has with a dry clean road surface varies with temperature as illustrated below.


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Some people keep two sets of tires - a winter set and a summer set - and switch them on the same wheels as the seasons change. While this is slightly better than keeping one set of tires all year around, consider this - every time you switch the tires you stand the risk of damaging the bead of the tire as the tire is dismounted thus shortening its life expectancy. The bead is the lip of the tire that seals against the wheel rim. After you have paid to have the tires dismounted and the other set mounted and balanced, you are still left with an less than ideal tire for the winter the winter because it may be too wide. In the long run, it’s far more cost effective to buy a second set of wheels plus you will have the correct tire and wheel for the appropriate season.
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Useless Tires
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! m% Y2 G9 M5 I2 ySince you and your vehicle are only as good as your tires, get rid of the following tires - Retreads - Old - Cheap - Unevenly worn - Under/over inflated - Not circular - Bald patches - Cords wearing through - Cracked - Bulging - and tires that are sized incorrectly for the wheel rim.

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