Blackcircles.com Tyre Glossay D-O
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Directional Tyres(also see asymmetric): This type of tyre must be fitted in an indicated orientation. Chevron or arrow shaped patterns are often used to help remove water from under the tyre.
Economy Tyres: (budget tyres) New tyres of fair quality which retail cheaper than mid range tyres (link). As you would expect performance will also be lower
Footprint (also see Contact Patch): The area of tyre tread that is in contact with the road surface
Hysteresis: In reference to Actions and reactions: not all energy applied to a tyre is dispersed. When dealing with an elastic material like rubber energy is always absorbed and this creates heat build-up.
Inner Liner The layer of rubber inside a tubeless tyre which stops air seeping out of the tyre during normal use
Load Index: Indicated on the Tyre Wall a standardized numerical guide that indicates the maximum weight a tyre can carry at the speed specified by its speed rating under conditions specified by the manufacturer.
Low Profile Tyres: These are tyres with shallow sidewalls usually fitted to high performance vehicles
Maximum Inflation pressure: Exactly what it says, the maximum pressure a tyre can be inflated too.
Mid Range tyres: Tyres which retail at a lower price than premium brands the performance of this range shall logically be lower
“Mini” Spare (also known as A Space Saving tyre): Smaller than the road tyres, this type of Tyre is designed to save space and reduce weight in the vehicle. A temporary measure to get you home these tyres should be changed as soon as possible, these tyres also have a lower maximum speed.
“M+S” Tyre: Tyres which have been designed to perform better in Mud and Snow
Nominal Section Width: The section width of an inflated tyre mounted on its theoretical rim and indicated in the tyre size designation.
Nominal Rim Diameter: A size code figure for reference purposes only, as indicated in the tyre and rim size designation.
Original Equipment (OE): This is the original brand of tyre that was fitted by the car manufacturer. Please not that there may be more than one OE brand fitment.
Oversteer (see also Understeer): This is a term used to describe a loss of grip to the rear wheels during cornering causing the car to slide sideways.