AVON RACING TYRES
THE OTHER day we drove to Melksham to see how Avon Tyres Limited make their racing tyres. The new Avon racing tyre department was opened in September last year, and occupies a 30,000 square-foot building, ripe for production expansion, on Avon’s 28-acre site where car, motorcycle, truck, tractor and industrial and farm-vehicle tyres are made by this independent, all-British manufacturer.
Avon won a proud place in racing many years ago, particularly in the motorcycle field, and Kaye Don was testing Avon tyres on the giant Wolseley Viper racing car in the 1920s, preparatory to winning the first, much-publicised RAC Ulster Ti race on Avon tyres in a supercharged Hyper Lea-Francis. In later years the Aston Martin sports / racing cars ran on Avons, and drivers of the calibre of Stirling Moss, Roy Salvadori, Tony Brooks, Peter Collins, Reg Parnell, etc. did well on them, including a Le Mans victory and winning a World Sports-Car Championship. Similiarly, in the motorcycle-racing world, riders like Duke, Suttees, Minter, Hailwood, Read, Hartle, and many others scored on Avon tyres and between 1958 and 1963 every solo motorcycle champion used them, so that Avon could claim 31 such championships and 77 records, the special tyres used helping materially in the development of the famous Roadrunner and the later V-rated Avon Venom tyres.
This year Avon tyres were used on the Aston Martin Nimrods at Co Mans, Avon-shod cars were in a dominating position in the RAC British Hill-Climb Championship, Barton and Cutmore used Avons in the European Sidecar ‘Championship, as did 14 entrants in the Silverstone Sidecar GP, Hot-Rod World Champion Davey Evans likewise, 25 out of 34 finishers in this Championship being on Avon tyres.
Avon have been prominent in rallying and, in 1969, Crossle cars using standard off-the-shelf Avon low-profile covers won the European FF Championship. Although Avon has recently dropped out of Fl racing, in which they supplied tyres to ATS, Theodore, Ensign and March teams this year, their tyres are still in wide demand for F2, F3, saloon-car racing, and on racing motorcycles and on sidecar outfits, Hot-Rods, etc. Incidentally, Avon 350 X 19 4-rayon-ply Triple Duty Mk. II tubed sidecar tyres are ideal for the earlier Austin 7s, and have an excellent tread-pattern.
Gordon Morris introduced us to Eddie Wood, technical manager Racing Tyres, who showed us some of the stages involved in their manufacture. Although the racing shop has been made as self-sufficient as possible, certain materials such as mixed rubbers for the various parts of the tyre and calendered fabrics for the reinforcing plies are prepared in other parts of the facto,. Within the racing shop a bias-cutter is used to give the designed bias angle to the normally-used nylon plies, the subsequent layering of which gives the cross-ply construction of the racing tyre. Rubber for treads is extruded in the shop, the rubber first being masticated on two 60-inch mills in train to raise the temperature and further improve the consistency, passing then through an extruder which pushes the hot rubber through a die to give the required tread profile. Depending on the size and type of racing tyre, this extruded tread rubber is varied in width from 0.2 to 0.7 metres. The continuous strip of extruded tread is fed along conveyor-belts through a cooling tank so a cutter, which automatically cuts the treads to
the required length.
The tyres are assembled on profiled collapsible metallic drums, so wide that, were it not for the small diameter, one might think they were for commercial vehicle covers, building up being semi-automatic.
Apart from the uses already mentioned, Avon tyres are fitted to hill-climb and Autocross cars and since 1975 the Avon Racing Department has operated modern warehouse and office facilities, and has established a comprehensive World-wide network of specialist dealers and the essential race-track service. The impressive Racing Tyre building can turn-out upwards of 1,200 specialised tyres a week. The all-British company was founded nearly 100 years ago and now has an annual turnover approaching £90-million, exports and overseas sales valued at almost £23 million being achieved in 1981, when more than 2, million tyres were produced by some 3,000 employees.
Reverting to the processes involved in making Avon racing tyres, in the factory that was erected in a mere six months from design to completion, the tread-line was specially installed for making racing tyres. The built uncured or “green” tyres are then put into moulds in Bag-o-Matic presses to give the finished shape, heat causing the chemical changes or “curing”. Inflation then ensures that heat-shrinkage is obviated and all that remains of a very skilled operation, from which the cost of such tyres stems, is the removal of the “spew-pips”, clearly seen in the photograph, examination for any defects, and dispatch to the customer.
Avon have a fascinating Tyre Museum that traces the Company’s histo, in particular, and tyre evolution in general which proved a great interest to me, betOre I drove away from this justifiably proud Wiltshire company.