Kia EV2: Tyres and wheels / Tyre terminology and definitions

Refer to the following comprehensive technical reference list for detailed definitions of the specialized terms found in the tyre descriptions and engineering documentation for your Kia EV2:

Air Pressure

The dynamic amount of compressed air inside the tyre pressing outward against the inner liner and supporting the vehicle structure. Air pressure is officially expressed in pounds per square inch (psi) or kilopascals (kPa), playing a critical role in optimizing the driving range and overall energy efficiency of the Kia EV2.

Accessory Weight

The combined mass of optional factory and dealer-installed accessories fitted to the vehicle. Some common examples of optional accessories integrated into modern electric vehicles like the Kia EV2 include advanced reduction gear systems, power-adjustable seats, and high-capacity automatic climate control units.

Aspect Ratio

The mathematical relationship of a tyre’s sectional height expressed as a percentage of its sectional width, directly influencing sidewall flexibility, cornering stability, and ride comfort.

Belt

A robust rubber-coated layer of high-tensile cords located directly between the internal carcass plies and the outer tread surface. These structural reinforcing cords may be manufactured from high-grade steel or other durable synthetic reinforcing materials designed to maintain tyre footprint integrity under high centrifugal forces.

Bead

The reinforced inner edge of the tyre containing endless high-strength steel wires wrapped securely by steel cords, engineered to mechanically lock and hold the tyre tightly onto the wheel rim flange under all driving loads.

Bias Ply Tyre

A traditional pneumatic tyre construction in which the internal structural plies are laid at alternating angles of less than 90 degrees relative to the centerline of the tread pattern.

Cold Tyre Pressure

The precise amount of air pressure contained within a tyre, measured accurately in pounds per square inch (psi) or kilopascals (kPa) before the vehicle has been driven and before any operational heat has built up from road friction.

Kerb Weight

The total baseline weight of a fully operational motor vehicle equipped with all standard and optional equipment, including maximum operating capacities of essential fluids like brake fluid and coolant, but without passengers or cargo onboard.

GVWR

Gross Vehicle Weight Rating, representing the maximum total operating weight permissible for the vehicle as specified by the manufacturer.

GAWR FRT

Gross Axle Weight Rating designated specifically for the front axle assembly, ensuring structural safety and proper load management for the Kia EV2.

GAWR RR

Gross Axle Weight Rating designated specifically for the rear axle assembly, establishing safe weight distribution limits for the chassis.

Intended Outboard Sidewall

The specialized side of an asymmetrical tyre designed and marked to face outward toward the exterior environment whenever the assembly is correctly mounted on the vehicle.

Kilopascal (kPa)

The standard international metric unit used for measuring pneumatic air pressure levels within automotive tyres.

Light truck (LT) tyre

A specialized heavy-duty tyre designated by its manufacturer as primarily intended for structural use on lightweight commercial trucks or multi-purpose passenger transport vehicles.

Load rating

The maximum carrying capacity that a specific tyre is structurally certified to support under a given inflation pressure parameter.

Load Index

An assigned numerical code ranging from 1 to 279 that directly corresponds to the maximum weight-carrying capacity of an individual tyre under specified engineering standards.

Maximum Inflation Pressure

The absolute maximum cold air pressure limit to which a tyre may be safely inflated, which is permanently molded directly onto the external sidewall structure.

Maximum Load Rating

The ultimate load-carrying capacity assigned to a tyre when it is inflated to its maximum allowable inflation pressure specification.

Maximum Loaded Vehicle Weight

The comprehensive sum of the vehicle kerb weight, total accessory weight, designated vehicle capacity weight, and installed production options weight.

Normal Occupant Weight

A standardized calculation representing the total number of occupants the vehicle is designed to seat multiplied by an average weight factor of 68 kg (150 lb) per person.

Occupant Distribution

The specific designated seating positions allocated across the cabin layout of the vehicle during transit.

Outward Facing Sidewall

The exterior side of an asymmetrical tyre that faces outward when mounted on a vehicle. The outward facing sidewall typically features high-contrast white lettering or manufacturer, brand, or model name moldings that are deliberately cast higher or deeper than the corresponding markings on the inner facing sidewall.

Passenger (P-Metric) Tyre

A standard pneumatic tyre category primarily utilized on passenger cars, modern electric hatchbacks like the Kia EV2, and selected light-duty utility vehicles.

Ply

A single structural layer of rubber-coated parallel reinforcing cords running through the carcass of the tyre.

Pneumatic tyre

A complex mechanical device engineered from rubber, specialized chemical compounds, structural fabric, and steel or other high-strength materials that, when mounted securely on an automotive wheel rim, provides essential road traction and encloses the pressurized gas or air that sustains the vehicle load.

Production options weight

The combined weight of installed regular factory production options weighing over 2.3 kg (5 lb) more than the standard factory components they replace, which were not previously accounted for within the baseline kerb weight or accessory weight calculations. Examples include heavy-duty braking components, electronic ride levelers, roof racks, high-capacity auxiliary batteries, and specialized interior trim packages.

Recommended Inflation Pressure

The vehicle manufacturer's officially recommended tyre inflation pressure levels, clearly displayed on the official vehicle tyre placard to ensure optimal safety and performance for your Kia EV2.

Radial Ply Tyre

A modern pneumatic tyre construction in which the internal structural ply cords extend outward to the beads at a 90-degree right angle to the centerline of the tread profile.

Rim

The precision-engineered metal structural support wheel upon which the rubber tyre beads are firmly seated and sealed.

Sidewall

The protective outer structural portion of a tyre situated vertically between the outer tread crown and the inner bead clamping area.

Speed Rating

An alphanumeric safety code assigned to a tyre indicating the maximum continuous speed threshold at which the tyre is certified to operate safely.

Traction

The mechanical frictional grip generated between the rotating tyre contact patch and the road surface conditions.

Tread

The thick outer rubber portion of a tyre engineered with specific grooves and sipes that makes direct physical contact with the road surface.

Treadwear Indicators

Built-in narrow solid rubber bands, commonly referred to as “wear bars,” that become visibly flush across the tread pattern when exactly 1.6 mm (1/16 inch) of usable tread depth remains.

UTQGS

Uniform Tyre Quality Grading Standards, an official consumer information rating system that provides vehicle owners with standardized quality grades for a tyre’s tread wear performance, traction capabilities, and temperature resistance. These ratings are determined through strict government-regulated testing procedures and are permanently molded into the sidewall of the tyre.

Vehicle Capacity Weight

The total combined weight capacity calculated by multiplying the designated seating positions by 68 kg (150 lb) and adding the fully rated cargo and luggage payload limits.

Vehicle Maximum Load on the Tyre

The absolute maximum load transmitted onto an individual tyre resulting from the combined kerb weight, accessory weight, and maximum occupant and cargo payload capacity.

Vehicle Normal Load on the Tyre

The standard operational load imposed on an individual tyre, calculated by distributing each axle's proper share of the vehicle kerb weight, accessory weight, and normal occupant weight, and then dividing the resulting sum by 2.

Vehicle Placard

A durable compliance label permanently affixed to the vehicle structure displaying the official original equipment tyre sizing specifications and recommended cold inflation pressures tailored for your Kia EV2.