A recent BBC article explored the possibility of car tyres as we know them, being replaced by an ‘airless’ solid rubber tyre?

 

At Tyrenet we always try to stay informed and aware of issues and developments that could affect our national network of qualified tyre dealers and fitters or truck tyre fleet management so hopefully, you may find this of interest too.

 

At the moment the technology seems to be related only to cars but as a lot of our commercial fleet managers also ask us to look after their cars and as many smaller commercial van fleets are also small vans, it well impact in the future.

 

The new tyres that in profile, look more like a bicycle tyre or a space saver emergency van tyre, are lighter and bonded to the wheel.

The BBC suggests that “sometimes it's difficult not to feel tyres are a car's weak link” and wonders if this technology will create a change?

The traditional air filled tyre was first used on vehicles in the 1890s and was designed to be indestructible, and therefore by definition they are not easily recycled.

 

The new generation of tyres has a degree of flexibility not in the tyre but in the special plastic spokes, which in turn support a thin, reinforced rubber tread. The spokes flex and contort as the car goes through its paces which does create noise and some vibration and there is much research being done to ‘soften the ride’.



Puncture-proof, recyclable, and have sensors that map road conditions

The BBC article recognises that “Electric cars and autonomous mobility are changing tyre needs. Delivery firms and shuttle services want products that are low-maintenance, puncture-proof, recyclable, and have sensors that map road conditions.”  There could therefore be a reduction in 24 hour emergency van tyre service requirements from dealers and tyre fitters but this is likely to be still some way off in the future and is less likely to affect commercial vehicles.

 

Businesses such as Goodyear are developing the technology partly because they are anticipating the trend towards a world “where autonomous vehicles are becoming more common and many cities are offering transport-as-a-service strategies, having a maintenance-free tyre is hugely important," a spokesperson said.

 

Whilst a call out for a car or van tyre repair might be less frequent with solid tyres, the converse will be that any issues will result in roadside assisted commercial tyre or wheel replacement as in effect the issue will result in a damaged wheel rather than just a replacement tyre.  In that case, much as it is today, there will still be a need for an emergency commercial tyre call out but to replace the wheel rather than the tyre.

 

Many well-known brands are developing airless tyres including Michelin, who have been working with General Motors (GM) on airless tyres since 2019. In February, there were media reports that Michelin's Unique Puncture-proof Tire System (Uptis) could debut on a new Chevrolet Bolt electric car being planned by GM, possibly as early as 2024 and as a result Michelin has filed 50 patents, according to the BBC article.

 

Michelin has been a market leader in airless wheels. Its Tweel (tyre-wheel) has been around since 2005 and is used on slow-moving vehicles, such as farm equipment.


Apart from occasional re-treads, the Tweel would be zero-maintenance, according to Michelin.

An additional consideration is that “heavy battery weight means airless structures are particularly suited to electric vehicles. "You can carry more load with a more compliant feel than in an air tyre," Mr Rachita of Goodyear says.

 

“On the other hand, airless tyres have a greater contact patch with the road, increasing the drag. This rolling resistance uses more energy to drive the tyres forward - with implications for battery life and range”, The BBC article added.”


‘And then there's noise - the hum of rubber-on-road’

"With engine sound removed on an electric car, tyres become the dominant source of noise," says Matt Ross, editor-in-chief of Tire Technology International.

 

In addition, “the rigidity of plastic spokes transmits more vibration through the suspension. Drivers long used to the response and performance of air tyres could take some convincing”, he feels.

 

“No Doubt Governments will demand rigorous safety tests and a standardisation of rules. And tyre makers will need to invest heavily in new manufacturing facilities and develop supply chains. It will take years”, the BBC article suggests.

 

Tyre makers hope early adopters in niche areas will help drive the technology forward. "Non-pneumatic tyres (NPTs) are of particular interest to sectors like the military, disaster response, security vehicles, and specialist machinery," Klaus Kraus, head of European research and development at Hankook, told BBC News.

 

The South Korean company unveiled the latest version of its i-Flex NPT in January. Smaller than a conventional tyre, a honeycomb of interlocking polyurethane spokes is a breakthrough in coping with lateral and horizontal stresses, the company says.


The future for mobile van tyre fitting

In the short term this technology is unlikely to affect mobile van tyre fitting, in the medium term it is likely to require greater stock levels as a multitude of solutions will be required for van tyre mobile fitting of both airless and conventional tyres.  In the longer term, there is a possibility that fleet management services may be affected by reduced failure, although all of the discussions and development to date have related to cars and we don’t envisage the local commercial tyre fitters to be impacted for a long time to come.