The world of rock climbing is abuzz with the arrival of a new, ultra-sticky shoe rubber, crafted from the very tires that power Formula One cars. This innovative material, developed by Japanese climbing company Ratom, has the potential to revolutionize the sport, making once-daunting slab routes accessible and transforming the way climbers approach their sport. But is it a game-changer, or just a fleeting trend? Let's delve into the details and explore the implications of this groundbreaking technology.
A Racing Tire's Second Life
Ratom's GP Rubber is made from retired racing slicks, the same tires that launch high-speed cars to incredible speeds. This unique material is then transformed into flat sheets, which are cut into climbing soles by affiliated resolers. The result? A rubber that is significantly stickier than any climbing rubber currently on the market. But what makes this innovation truly fascinating is its origin story.
Katsuhito Arai, the founder of Ratom, is a former motorcycle racer who drew inspiration from his own experience. He envisioned a climbing shoe that could match the grip of racing slicks, and thus, the idea for GP Rubber was born. By using retired racing tires, Ratom not only creates a highly effective climbing rubber but also promotes sustainability, giving a second life to materials that would otherwise be discarded.
Testing the Stickiness
To evaluate the performance of GP Rubber, I put a pair of Five Ten Moccasyms with a GP1-hard half-sole to the test at my local bouldering gym and on medium-coarse Leavenworth granite. The results were impressive, with a definite increase in sticking power on small, sloping footholds. However, the rubber seemed to hold up less well on volumes, where it required more force to activate a better grip.
One of the most intriguing aspects of GP Rubber is its temperature responsiveness. As it warms up, its sticking power increases significantly, making it ideal for climbers in colder climates. However, this increased stickiness also means it deforms more easily, making it less effective for edging. This temperature-dependent behavior opens up a new realm of temperature-beta for climbers, allowing them to optimize their shoe game throughout the day and year.
The Future of Climbing Shoe Rubber
Ratom's rubber raises an interesting question: How soft can climbing rubber go? According to Ratom, their rubber ranges from 55A to 65A on the Shore A hardness scale, significantly softer than other popular climbing rubbers. However, softness is not the only factor when it comes to stickiness. A 2024 paper in the journal Sports Engineering found that Five Ten's Stealth C4 rubber performed second best in one test of sticking power, despite being one of the hardest rubbers tested. This suggests that molecular adhesion and surface roughness also play a crucial role in determining stickiness.
While GP Rubber may not revolutionize climbing or negate the need for good footwork, it does offer significant improvements in grip in specific environments, such as friction slabs and small, sloping footholds. For the dedicated shoe nerd, GP Rubber is worth having in your rotation, as it can be used in conjunction with other rubbers to optimize performance. However, for beginner climbers, the grippier rubber could make up for poor foot technique, while advanced climbers may find specific uses for different GP compounds on difficult projects.
In conclusion, Ratom's GP Rubber is an exciting development in the world of rock climbing, offering a unique combination of innovation, sustainability, and performance. While it may not be a game-changer for everyone, it certainly has the potential to enhance the climbing experience for many. As the technology continues to evolve, we can expect to see more innovative uses for this groundbreaking material.
