Making the Tyres

A very British motorbike

Making tyres is a complex process. Here is a brief guide to how it is done. All pictures are courtesy of Avon Tyres. Thanks chaps.

The control unit for the Avon Tyres BanburyThe first stage is to mix the raw materials which go to make up the tyres. Natural rubber accounts for approximately 40 per cent of the content. Three different types of synthetic rubber are used. Other major components are Carbon Black (durability and colouring), Silica (wet weather grip, reduction in friction) and various chemicals used to fine tune the composition. This is the control unit of the mixer.
Milling the rubber used for the manufacture of Avon tyresThe various different types of rubber to be used in the building of the tyres are milled into strips of consistent thickness and width. They are checked for consistency throughout the process. The progress of each batch of rubber is tracked by computer to ensure that the correct blends of rubber are used for each different model of tyre produced and delivered to the appropriate assembly areas in the factory.
Milled sections of rubber cut to length at Avon TyresThe milled sheets of rubber are seen here waiting to be cut to the exact widths and lengths required for tyre construction. Further inspection is carried out at this stage and any imperfections removed.
Layers of rubber being built onto the drum at Avon TyresTyres are built on a drum. The first sheet is an airtight synthetic rubber, followed by the main casing, the bead and finally several layers of compound and the sidewalls.
Completed tyre on the drum at Avon Tyres UKOnce the layers are completed, the flexible centre of the tyre building drum is expanded which causes the outer surface to assume the profile of the finished tyre.
Green tyres being cured at Avon Tyres in Melksham UKGreen tyres, as they are referred to at this stage of construction, are removed from the building drum and stored ready for the curing process. Note the lack of tread at this point.
The final stage of the tyre building process at Avon Tyres UKFor the final part of the process, the tyres are inserted into moulds and cured under pressure at a heat of 170°C. The tyres are cured by chemical reaction. It is at this stage that the treads are formed and the lettering is embossed into the sidewalls. This final part takes around fifteen minutes to complete.
Avon tyres mounted on Dymag wheels for the Enigma 1050Finally, we can see the tyres on the Dymag wheels. We have opted for a 180/55 rear which we think is plenty big enough. We could go to a 190 but it would slow the steering down too much.

That is a quick outline of how tyres are made. We cannot reveal the exact composition of the tyres nor can we show every fine detail of manufacture as these are well guarded trade secrets. Our thanks to Avon for providing the pictures for this page and for letting us have a pair of Avons for Enigma 1050. Let’s keep it as British as we can. Find out more about Avon tyres here.

Enigma 1050 – a very British motorcycle being built in Hampshire, Derbyshire, Leicestershire, Berkshire, Wiltshire, Surrey, Sussex, Suffolk, Shropshire and Cambridgeshire.