WRC
From design to the stages: Hankook lifts the lid on WRC tyre development
Tyres are integral to success in the FIA World Rally Championship, in what is arguably the most demanding championship in global motorsport.
These circular pieces of rubber have to cope with the harshest of conditions and terrains. Whether it is the icy asphalt of Monte Carlo, the below-freezing snowy stages of Sweden, the muddy savannahs of Safari Rally Kenya, the ultra-fast gravel of Finland or the harsh rocky stages of Acropolis Rally Greece, the tyres have to perform. So how does Hankook achieve this monumental task, which is among the toughest jobs in motorsport?
The Korean company opened its doors to its state-of-the-art facilities in Korea to lift the lid on how it develops its tyres from a design concept to the stages. Hankook produced its first motorsport tyre in 1992 and developed its first rally tyre for national series in Greece and Italy in 2000. It has become one of the global leaders in motorsport, having supplied tyres to major championships such as DTM and FIA Formula E before moving into the WRC from 2025.
Developing tyres to compete in the WRC is far from simple. In a nutshell, it can take from 12 to 18 months to develop a WRC tyre from the initial design phase before it appears among the allocation for WRC drivers and teams to select and utilise on events. However, Hankook does have the ability to fast-track the process if urgent changes are required.
Hankook's state-of-the-art Technodome facility
© Hankook
The crux of the work is carried out at Hankook’s stunning space-age 98,000 sqm Technodome research and development facility located in Daejeon, two hours from the capital city Seoul. The building was designed by famous British architect Norman Foster and constructed in 2015. Approximately 1,160 employees work at the facility, with a large number living in residence on site. In order to cater for the wellbeing of its employees, the Technodome is not simply a place of work. Eating facilities, a library, convenience stores, a gym and a wellness centre are built into the facility to create a healthy working environment.
“I think you can see the commitment to people when you look at our facilities,” said Hankook’s WRC representative Steven Cho. “The point of the facilities is to have a really good working culture and a working environment, because in any business, whether it’s tyres or anything, it’s all about people. So we need to have the best people and we need them to be happy and motivated. All of those efforts that you see, I think reflect those priorities, that people are everything.”
It is inside the Technodome nerve centre where all of Hankook’s tyres, from production road car rubber to circuit racing and rally tyres, are conceived. Every specification of tyre undergoes meticulous research and development before it begins virtual and real-world testing.
© Hankook
The process begins with an analysis of the conditions in which the tyre is required to perform, before a technical plan and specification for the tyre is produced. This includes determining the tread pattern, profile, compound and structure.
The tyres themselves are composed of approximately 10 to 15 different compounds, and each compound is developed by blending around 10 to 20 different raw materials. These materials can generally be categorised into natural rubber, synthetic rubber, fillers such as carbon black and silica, plasticisers including oils and resins, and vulcanising agents. Each category also contains a wide range of material types depending on their chemical structures and physical characteristics. At the laboratory stage, various combinations and formulations of these raw materials are tested and optimised to develop compounds that achieve the targeted performance characteristics.
Once a specification of tyre is selected, indoor testing and simulations of structure, performance and durability are carried out before the tyre passes to the next step of the process: real-world testing on the stages in Europe conducted by the WRC teams. Once validated by the teams and Hankook, mass production of the tyre begins, with the tyres produced in a separate factory, also located in Daejeon. Production usually commences five months before each rally to ensure enough time for the tyres to be produced and freighted to events for competitive use on the stages.
© WRC
What does the future hold for Hankook’s WRC tyres?
Now into its second season as the WRC’s official tyre supplier, the development work to hone its knowledge gained on the stages and make even better tyres continues. Earlier this year, the brand introduced a new soft compound gravel tyre, but there are more changes on the way.
Hankook has now revealed that it will introduce an all-new winter asphalt tyre, known as the SR20A, and a new studded ice tyre, the SR11, to its range for next year. The asphalt tyre will feature wider grooves to improve the evacuation of snow and slush, and a new compound better designed to deal with cold temperatures.
Likewise, the new ice tyre will be built to a new profile and structure to improve stability and handling while running in ruts. Work to improve stud retention has also been carried out. Both tyres have received positive feedback from teams, with the development testing being carried out by current Rally1 cars that will be phased out as the WRC moves to new technical regulations in 2027.
While these tyres are regarded as all-new products for 2027, development will continue on Hankook’s current asphalt and gravel tyres, with changes expected to be made.
“For the tarmac hard we are developing a new compound to improve the grip and for the wet we are also developing a new compound to improve grip in the cold conditions, for like 2-5 degrees Celsius. We are also developing a structure for the tyre to improve the handling and durability of the wet tyres,” said Kim Hyeyongi, Hankook WRC R&D engineer, during a media Q&A at Hankook’s research and development facility in Korea.
© WRC
“For the gravel we are focusing more on the durability for the gravel hard tyres. The hard compound is normally used in the tough and harsh rallies like Greece, Portugal and Sardinia.”
How can lessons learned in the WRC translate to everyday drivers?
Of course, lessons learned in the harshest environments on the stages will be logged and utilised for future road car tyre development, bringing the knowledge gained from the WRC to the average motorist on the road.
“I think being in the WRC is very important [for developing our road car products for customers],” Cho added.
“The technical requirement of the tyres for the WRC is just crazy. There’s really no real-world street application for those types of tyres. The tyres and the physical product itself are very different from what we’re actually putting on standard street cars, but there are also a lot of learnings on process and materials and people.
WRC tyres must withstand some of the toughest terrain in motorsport
© WRC
“So all of the challenges that we’re dealing with here in the WRC on a daily basis require us to come up with solutions. What we often find is that a solution to a similar problem that could have been on a street tyre or a truck tyre sometimes has directional solutions that work in rally and the other way around.
“We’re dealing with having to find solutions for the Rally1 car, for example. That direct solution may not have application anywhere else today, but the directional solution that we find to solve that problem can be utilised in other areas, so for sure, there is a direct correlation there. The speed that we have to work to take feedback and data from the teams and drivers and ideate that into a solution, develop a prototype to be tested and validated, that’s the same as a normal development cycle. There are definitely learnings there on the process side. And there’s no better place to develop people than in the heat and intensity of the WRC.”
