ALL-SEASON TYRES
Tyres that provide adequate traction on snow and ice without compromising performance in milder conditions.
ARAMID
A synthetic fabric used in some tyres that is stronger than steel.
BEAD STRIP
A key tyre component that forms the contact point between the tyre and the rim, designed to withstand the forces exerted during fitting and the dynamic forces from driving and braking.
BEAD FILLER
Responsible for transferring driving torque and braking force from the rim to the contact area with the road surface.
BEAD TENSION STRUCTURE
Two side plies wrapped around each bead wire in opposite directions, providing lateral stability while remaining flexible to absorb road irregularities.
BELT
A layer of cords coated in rubber located between the carcass plies and the tread. Cords are usually made of steel but can also be made from fiberglass, rayon, nylon, polyester, or other fabrics.
DIAGONAL CARCASS
A type of tyre with plies laid diagonally across the tyre relative to the tread centreline.
BOLT CIRCLE
The diameter of an imaginary circle drawn through the centre of each wheel nut hole, measured between two holes directly opposite each other. This measurement is used to select the correct wheel for replacement.
BRAKING TORQUE
A technique used by drivers and during road tests to improve initial acceleration. It involves pressing the brake and accelerator simultaneously, increasing engine speed until the brake is released.
SLIP
A term used to describe a loss of traction when cornering or accelerating from a standstill. The tyres slide against the road surface rather than gripping it.
BUTYL RUBBER
A synthetic rubber used in modern tyre manufacturing, virtually impermeable to air and water.
CAMBER
The tilt of a wheel inward or outward relative to vertical, measured in degrees. Camber is adjusted to keep the outer tyres flat on the road during cornering.
CAMBER THRUST
The lateral force generated when a tyre rolls with camber, which can add to or subtract from the lateral force produced by the tyre.
CARBON BLACK
A reinforcing filler incorporated into the rubber compound of the tyre to provide resistance to wear.
CARCASS
The load-bearing structure of the tyre, consisting of plies anchored at one bead and radiating across to the other bead.
CARCASS PLY
Thin textile cords embedded in rubber, largely responsible for the tyre’s strength.
LOAD CAPACITY
The weight each tyre is designed to support at a given air pressure. For every tyre size, a load-inflation table ensures the pressure used is sufficient for the vehicle’s axle load.
CASTER
The angle between a vertical line through the wheel centre and the steering axis; improves directional stability and steering feel.
CENTRELINE
An imaginary line at the centre of the vehicle. Wheel alignment measurements are taken relative to this line.
CENTRIFUGAL FORCE
The lateral acceleration, measured in g, of an object moving along a curved path. When a car corners, centrifugal force acts outward, which tyres counteract by developing an equal and opposite force against the road. Also called lateral force.
CORD
The strands of fabric forming the plies or layers of a tyre. Cords can be polyester, rayon, nylon, fiberglass, or steel.
CORNERING FORCE
The force exerted on a vehicle’s tyres when cornering. It represents the tyre’s ability to grip and resist lateral forces to keep the vehicle on its intended path.
CAP PLYS
Provide a rigid base for the tread, contributing to fuel efficiency, centrifugal and lateral stiffness, while allowing flexibility for a comfortable ride.
CURB WEIGHT
The weight of a standard vehicle with full fluid tanks (including fuel) and all standard equipment, but without passengers or cargo.
DIRECTIONAL STABILITY
The ability of a vehicle to travel straight at high speed safely and confidently, unaffected by road irregularities, crosswinds, aerodynamic lift, or other external forces.
MISALIGNED TRACKS
The track is the width between the outer edges of tyres on the same axle. Misaligned tracks occur when wheel alignment is off and rear wheels do not follow the front wheels in a straight line.
DRIFT
A vehicle deviating from a straight path without steering input.
ECCENTRIC MOUNTING
Fitting a tyre and wheel assembly so that the centre of rotation of the assembly does not align with the vehicle hub centre.
ZERO-DEGREE FILAMENT
Individual reinforcement filaments in nylon or aramid/nylon wound in spirals, precisely positioned in specific areas or across the tread on steel belts set at zero degrees. This maintains tyre shape and improves ride quality and steering precision.
FRONT-TO-REAR WEIGHT TRANSFER
The transfer of weight from the front axle to the rear axle (or vice versa) caused by acceleration or braking. Acceleration shifts weight from the front to the rear; braking shifts weight from the rear to the front.
FOUR-WHEEL DRIFT
A handling term describing a car whose front and rear tyres slide in a controlled manner. The driver uses throttle and steering to maintain the vehicle on a prescribed line.
UNLOADED RADIUS
The radius of the tyre/wheel assembly when not under load.
GROSS AXLE WEIGHT RATING (GAWR)
The maximum weight that can be distributed across the tyres on a given axle.
GROSS VEHICLE WEIGHT RATING (GVWR)
The weight of the vehicle and its contents (fluids, passengers, and cargo).
VEHICLE GROSS WEIGHT RATING
The maximum allowed weight of the vehicle and its contents, as specified by the manufacturer, and usually indicated on the door pillar label.
NOTCHING
A normal and safe phenomenon on a tyre sidewall where overlapping ply splices create small notches. This does not occur on the tread due to steel belt placement.
INNER LINER
The innermost layer of a tubeless tyre, made of nearly impermeable butyl rubber. Over time, air loss can occur, so tyre pressures should be checked monthly to ensure proper function and reliability.
LATERAL WEIGHT TRANSFER
When cornering, weight shifts from the inner wheels to the outer wheels due to centrifugal or lateral forces.
LOADED RADIUS
The measurement in inches from the axle centre to the ground when the tyre is properly inflated for its load.
LOADED SECTION HEIGHT
The height of the tyre section in contact with the road.
LOAD RANGE
Specifies the range of maximum loads a tyre can support at a given inflation pressure.
HUB-CENTRED
Wheels are designed to fit the hub or bolts perfectly, ensuring the holes align correctly with the vehicle hub.
LUXURY TOURING PERFORMANCE TYRES
Typically designed for luxury sedans, these tyres balance handling capabilities with a smooth and comfortable ride.
OXIDATION
A rusting process that occurs in steel belts if moisture penetrates due to damage, which may cause premature tyre replacement.
ROLLING CIRCUMFERENCE
The linear distance a tyre covers in one rotation. This can vary depending on load and inflation. Calculated as 63,360 divided by the number of revolutions per mile = rolling circumference in inches.
RUBBER COMPOUND
A mixture of raw materials blended using carefully developed processes, tailored to the performance requirements of each tyre type.
STEEL BELT
A layer of steel cords coated in rubber, forming a belt placed under the tread and over the carcass; it ensures uniform rotation and helps prevent punctures.
STEERING RESPONSE
The vehicle’s reaction to the driver’s steering inputs. The feedback received through the steering wheel during manoeuvres.
SYNTHETIC RUBBER
Artificial rubber, as opposed to natural rubber. Most modern passenger car and van tyres contain a relatively small proportion of natural rubber.
ALIGNMENT
The difference in distance between the front and rear of a pair of tyres on the same axle.
TOE-IN
The front of two tyres on the same axle is closer together than the rear.
TOE-OUT
The front of two tyres on the same axle is farther apart than the rear.
STEERING ANGLE IN CORNERS
Also called Ackermann angle. The inner wheels follow a smaller radius than the outer wheels in a turn, as the two front wheels have different steering angles.
FORCE
Torque or turning effort, usually measured in lb-ft or Newton metres.
TORSION BAR
A long straight bar attached to the frame at one end and a suspension part at the other; acts as an untwisted spring absorbing energy through torsion.
TREAD UNDERLAY THICKNESS
Material between the bottom of the tread rubber and the top of the steel belts; acts as a cushion for improved comfort.
VARIABLE CONTACT PATCH
A system that maximises the contact area in corners through a combination of asymmetrical tread patterns and underlying belts.
WHEELBASE
The longitudinal distance between the centre of the front wheel and the centre of the rear wheel on the same side of the vehicle.
Tyres that provide adequate traction on snow and ice without compromising performance in milder conditions.
ARAMID
A synthetic fabric used in some tyres that is stronger than steel.
BEAD STRIP
A key tyre component that forms the contact point between the tyre and the rim, designed to withstand the forces exerted during fitting and the dynamic forces from driving and braking.
BEAD FILLER
Responsible for transferring driving torque and braking force from the rim to the contact area with the road surface.
BEAD TENSION STRUCTURE
Two side plies wrapped around each bead wire in opposite directions, providing lateral stability while remaining flexible to absorb road irregularities.
BELT
A layer of cords coated in rubber located between the carcass plies and the tread. Cords are usually made of steel but can also be made from fiberglass, rayon, nylon, polyester, or other fabrics.
DIAGONAL CARCASS
A type of tyre with plies laid diagonally across the tyre relative to the tread centreline.
BOLT CIRCLE
The diameter of an imaginary circle drawn through the centre of each wheel nut hole, measured between two holes directly opposite each other. This measurement is used to select the correct wheel for replacement.
BRAKING TORQUE
A technique used by drivers and during road tests to improve initial acceleration. It involves pressing the brake and accelerator simultaneously, increasing engine speed until the brake is released.
SLIP
A term used to describe a loss of traction when cornering or accelerating from a standstill. The tyres slide against the road surface rather than gripping it.
BUTYL RUBBER
A synthetic rubber used in modern tyre manufacturing, virtually impermeable to air and water.
CAMBER
The tilt of a wheel inward or outward relative to vertical, measured in degrees. Camber is adjusted to keep the outer tyres flat on the road during cornering.
CAMBER THRUST
The lateral force generated when a tyre rolls with camber, which can add to or subtract from the lateral force produced by the tyre.
CARBON BLACK
A reinforcing filler incorporated into the rubber compound of the tyre to provide resistance to wear.
CARCASS
The load-bearing structure of the tyre, consisting of plies anchored at one bead and radiating across to the other bead.
CARCASS PLY
Thin textile cords embedded in rubber, largely responsible for the tyre’s strength.
LOAD CAPACITY
The weight each tyre is designed to support at a given air pressure. For every tyre size, a load-inflation table ensures the pressure used is sufficient for the vehicle’s axle load.
CASTER
The angle between a vertical line through the wheel centre and the steering axis; improves directional stability and steering feel.
CENTRELINE
An imaginary line at the centre of the vehicle. Wheel alignment measurements are taken relative to this line.
CENTRIFUGAL FORCE
The lateral acceleration, measured in g, of an object moving along a curved path. When a car corners, centrifugal force acts outward, which tyres counteract by developing an equal and opposite force against the road. Also called lateral force.
CORD
The strands of fabric forming the plies or layers of a tyre. Cords can be polyester, rayon, nylon, fiberglass, or steel.
CORNERING FORCE
The force exerted on a vehicle’s tyres when cornering. It represents the tyre’s ability to grip and resist lateral forces to keep the vehicle on its intended path.
CAP PLYS
Provide a rigid base for the tread, contributing to fuel efficiency, centrifugal and lateral stiffness, while allowing flexibility for a comfortable ride.
CURB WEIGHT
The weight of a standard vehicle with full fluid tanks (including fuel) and all standard equipment, but without passengers or cargo.
DIRECTIONAL STABILITY
The ability of a vehicle to travel straight at high speed safely and confidently, unaffected by road irregularities, crosswinds, aerodynamic lift, or other external forces.
MISALIGNED TRACKS
The track is the width between the outer edges of tyres on the same axle. Misaligned tracks occur when wheel alignment is off and rear wheels do not follow the front wheels in a straight line.
DRIFT
A vehicle deviating from a straight path without steering input.
ECCENTRIC MOUNTING
Fitting a tyre and wheel assembly so that the centre of rotation of the assembly does not align with the vehicle hub centre.
ZERO-DEGREE FILAMENT
Individual reinforcement filaments in nylon or aramid/nylon wound in spirals, precisely positioned in specific areas or across the tread on steel belts set at zero degrees. This maintains tyre shape and improves ride quality and steering precision.
FRONT-TO-REAR WEIGHT TRANSFER
The transfer of weight from the front axle to the rear axle (or vice versa) caused by acceleration or braking. Acceleration shifts weight from the front to the rear; braking shifts weight from the rear to the front.
FOUR-WHEEL DRIFT
A handling term describing a car whose front and rear tyres slide in a controlled manner. The driver uses throttle and steering to maintain the vehicle on a prescribed line.
UNLOADED RADIUS
The radius of the tyre/wheel assembly when not under load.
GROSS AXLE WEIGHT RATING (GAWR)
The maximum weight that can be distributed across the tyres on a given axle.
GROSS VEHICLE WEIGHT RATING (GVWR)
The weight of the vehicle and its contents (fluids, passengers, and cargo).
VEHICLE GROSS WEIGHT RATING
The maximum allowed weight of the vehicle and its contents, as specified by the manufacturer, and usually indicated on the door pillar label.
NOTCHING
A normal and safe phenomenon on a tyre sidewall where overlapping ply splices create small notches. This does not occur on the tread due to steel belt placement.
INNER LINER
The innermost layer of a tubeless tyre, made of nearly impermeable butyl rubber. Over time, air loss can occur, so tyre pressures should be checked monthly to ensure proper function and reliability.
LATERAL WEIGHT TRANSFER
When cornering, weight shifts from the inner wheels to the outer wheels due to centrifugal or lateral forces.
LOADED RADIUS
The measurement in inches from the axle centre to the ground when the tyre is properly inflated for its load.
LOADED SECTION HEIGHT
The height of the tyre section in contact with the road.
LOAD RANGE
Specifies the range of maximum loads a tyre can support at a given inflation pressure.
HUB-CENTRED
Wheels are designed to fit the hub or bolts perfectly, ensuring the holes align correctly with the vehicle hub.
LUXURY TOURING PERFORMANCE TYRES
Typically designed for luxury sedans, these tyres balance handling capabilities with a smooth and comfortable ride.
OXIDATION
A rusting process that occurs in steel belts if moisture penetrates due to damage, which may cause premature tyre replacement.
ROLLING CIRCUMFERENCE
The linear distance a tyre covers in one rotation. This can vary depending on load and inflation. Calculated as 63,360 divided by the number of revolutions per mile = rolling circumference in inches.
RUBBER COMPOUND
A mixture of raw materials blended using carefully developed processes, tailored to the performance requirements of each tyre type.
STEEL BELT
A layer of steel cords coated in rubber, forming a belt placed under the tread and over the carcass; it ensures uniform rotation and helps prevent punctures.
STEERING RESPONSE
The vehicle’s reaction to the driver’s steering inputs. The feedback received through the steering wheel during manoeuvres.
SYNTHETIC RUBBER
Artificial rubber, as opposed to natural rubber. Most modern passenger car and van tyres contain a relatively small proportion of natural rubber.
ALIGNMENT
The difference in distance between the front and rear of a pair of tyres on the same axle.
TOE-IN
The front of two tyres on the same axle is closer together than the rear.
TOE-OUT
The front of two tyres on the same axle is farther apart than the rear.
STEERING ANGLE IN CORNERS
Also called Ackermann angle. The inner wheels follow a smaller radius than the outer wheels in a turn, as the two front wheels have different steering angles.
FORCE
Torque or turning effort, usually measured in lb-ft or Newton metres.
TORSION BAR
A long straight bar attached to the frame at one end and a suspension part at the other; acts as an untwisted spring absorbing energy through torsion.
TREAD UNDERLAY THICKNESS
Material between the bottom of the tread rubber and the top of the steel belts; acts as a cushion for improved comfort.
VARIABLE CONTACT PATCH
A system that maximises the contact area in corners through a combination of asymmetrical tread patterns and underlying belts.
WHEELBASE
The longitudinal distance between the centre of the front wheel and the centre of the rear wheel on the same side of the vehicle.