Unless you are a car mechanic, tyre technician or an absolute geek, there is a huge chance you don’t know much about the construction of a tyre. Few people wonder what parts typical car tyres are made of - and no wonder as there is a long way from driving a car to having such purely technical knowledge.

Even without being a geek, though, you may find it interesting to discover particular parts of tyres and their functions. Find out how different tyre construction methods are used in various types of tyres - not just conventional vehicles.

A close-up of tyre tread

A tyre is a more complicated product than you might think. It is built of several different elements which influence its parameters. To start with, we should distinguish between the basic tyre parts and the extra elements. Such a distinction will help to understand the influence of particular parts on a tyre.

Basic tyre parts

Inner liner

  • This is an air- and water-resistant layer of rubber which replaces the inner tube in tubeless tyres.
  • It is made of butyl (a type of synthetic rubber) which is an air-resistant mixture.
  • One of the inner liner’s main features is its high tolerance to oxidising agents, acids and alkalis.
  • It is intended to minimise the loss of air and to protect internal elements against air, ozone and water ingress.

Elements found within common tyre types.Elements found within common tyre types

Textile layer – carcass

  • This is a textile material composed of cord treads which make a unique tyre contour.
  • A passenger car tyre will consist of 1,2 or 3 textile layers, each between 1 and 1.5 mm in thickness.
  • The textile layer is intended to keep the tyre in shape under inner pressure and to transfer the tuning, braking and speeding workload.

Bead wires

  • These are rugged wires making several coils.
  • Bead wires make it possible to mount tyres on the rims.
  • Every tyre contains two bead wires surrounded by a layer of textile carcass.

Bead filler

  • A bead filler is a profiled rubber layer which stiffens the bead seat and ensures that the bead wire remains in place.
  • It is responsible for the wear life of a tyre, its steering behaviour and driver comfort.

Bead bundle

  • It ensures the resistibility of a tyre and its long wear life.
  • It separates the bead wire from the wheel rim.
  • The bead bundle is made of material that enables minimum wear during its constant contact with the wheel rim.

Side wall

  • Side wall is the rubber used to protect tyres. It shields them against any scratches, abrasions or other environmental factors, including ultraviolet rays, differences in temperature, chemical agents and more.
  • Anti-aging ingredients are the main component of the rubber mixture used for this particular part.
  • Steel belt
  • Steel belt consists of steel netting which forms the wheel armament.
  • There are typically two of these belts in a tyre.
  • The purpose of steel belts in radial tyres is to better forward the driver’s commands from the steering wheel to the road, improving the steering behaviour of a car.


  • Treads are designed to ensure good steering behaviour, adhesion, wear resistance, and good turning behaviour.
  • It also helps provide a reduction of both tyre rolling resistance and the volume of tyre noise.
  • The tread mixture includes synthetic and natural rubbers.
  • There are further thread elements, such as sipes, tread lugs, tread ribs and tread grooves.

Inner liner penetration of the textile cord threads.Inner liner penetration of the textile cord threads

Additional tyre parts

Isolation bundle

  • This is the rubber located on the edge of the belts which protects the carcass against damage that may be caused by the steel belt threads.

Cap ply

  • Cap ply is a textile material which forms a stabilising belt over the crown ply.
  • It is usually a narrow bundle that consists of several threads of rubber cord.
  • It is of great importance when it comes to the appropriate high speed resistance.

Rubber chafer

  • This is a profiled rubber layer placed both above and around the bead filler.
  • It helps to improve the car’s traction, strength and stiffness.

Bead reinforcement

  • This consists of textile and steel cord piles. Their role is stiffening the tyre bead seat.
  • These are used in so-called low bead tyre models.

Bead filler

  • Bead filler is a rubber supplement used as an undercoat, placed between the bead bundle and the NC layer.

Sidewall reinforcement

  • This is a rubber layer that strengthens the tyre in the inner shoulder zone, preventing inner liner penetration into the layer of textile threads.


  • This is a rubber layer reducing heat in the face of a tyre and protecting the steel belts.

The influence of tyre elements on the performance

Table with columns

There are many different elements that go into the construction of various parts of car tyres. The right combination of these can help improve your driving experience and comfort, among other factors.