Everybody has been guilty of taking their tyres for granted at some time in their motoring career, whether its running them at the wrong pressure, or unintentionally driving when the tread depth is beyond the legal minimum.
Having been tyre manager for my colleagues’ cars in the office over the past 15 years my role has been to make drivers aware when their tyres needs some TLC.
A recent puncture on my new Volvo XC60 R-Design SUV meant replacing the tyre to match the other three that were fitted as original equipment. I took it to the local dealer who was very helpful, but it took a wrong tyre order and a week before the correct tyre arrived. This began my education about new tyre technologies.
The tyre wasn’t just any old Michelin Latitude Sport 3. Unbeknown to the dealer the R-Design model has tyres with cavity noise damping which reduces noise, particularly on motorways.
Michelin Acoustic Technology makes use of custom-designed polyurethane foam solution that muffles noise resonance, effectively reducing road vibrations by a claimed 20%. It certainly makes the new XC60 enjoyable to drive long distances on the motorway. https://www.michelinman.com/US/en/why-michelin/michelin-acoustic-technology.html
Pirelli has shared some of the challenges when it comes to developing car tyres in its excellent blog (https://www.pirelli.com/global/en-ww/road/why-electric-cars-need-different-kinds-of-tyres). It admits to EVs pushing the boundaries of tyre technology.
Electric car tyres need to be grippy, but not too grippy that they sap vital battery power and the range of a car between charges. EVs are also very quiet, and the tyres’ acoustics need to match the characteristics of the car. The extra weight of heavy batteries in the EV also means tyre side walls must be strengthened as they endure extra stress while accelerating and cornering.
Tyres are playing a major part in the Worldwide harmonised Light vehicles Test Procedure (WLTP) regulations which go live in September for all new cars. A Real Driving Emissions test is being adopted, designed to replicate real-world journeys which measure a car’s NOx and particulate emission level much more accurately. A car’s weight, aerodynamics and tyre rolling resistance are also part of the testing procedure mix with each car given a unique CO2 figure based on the criteria.
A narrower tyre with stiff sidewalls performs better in the new testing protocol. Car companies are still working out the best car/tyre combination to generate the lowest CO2 figure for each model as a narrow tyre isn’t necessarily the grippiest.
So, the next time you get into your car give a little thought to those black round circles on each corner. Look after them as your friends, as they are the only touch point with the tarmac when you travel along the motorway at 70mph. You can also start to appreciate why some of the newest high-tech tyres cost more than your standard tyre, or from a brand you have never heard of before. Tyre technology is changing rapidly to keep up with speed of new car technology and one cannot survive without the other.