Kenda has introduced two new gravity tire models, the Hellkat Pro and Helldiver Pro, both featuring their new Advanced Gravity Casing (AGC) technology, which was developed to meet the specific demands of downhill racing on the World Cup circuit with influence and testing from members of the UR Racing Team, including UCI World Championship medalists Mick and Tracy Hannah. Features include:
- Enhanced tread puncture and sidewall cut resistance
- Low weight for wire bead downhill tire, with Hellkat Pro
- Tubeless ready
- Wire and folding bead options, with more constructions for enduro use in development
Technical Components of Advanced Gravity Casing
KVS – Kenda Vector Shield: Developed in joint cooperation between Kenda’s North American and Taiwanese engineering teams at the Kenda America Technology Center. The KVS is a woven sheet of aramid fibers laid up across the sidewall of a tire which offers a light-weight casing shield with a claimed 285% higher cut resistance than standard protective materials. This allows for a reduction in the casing weight by up to 200 grams when compared to traditional 2-ply downhill casings.
Because of the addition of the Kenda Vector Shield, the casing now offers superior cut resistance, while being stiffer and lighter at the same time. As a result, you can ride with a lower tire pressure, which increases the tread grip without risking a flat tire. Additionally, the KVS material is claimed to make the sidewall stiffer ensuring better feedback for the rider and improved predictability in handling.
ICB – Iron Cloak Belt: Light weight aramid belt under the tread to increase the puncture resistance by 18%. This reduces penetration in the tread surface from foreign objects, punctures from rocks and other debris, and reducing the chance of casing fractures. As a result of the inclusion of ICB and lower tire pressures the tread can more easily conforms to the trail surface to provide better grip and low rolling resistance. The center knobs in the tread area, directly above the ICB, are more flexible and provide a better grip and fast rolling.
20mm Apex: A rigid rubber insert on the top of the bead that stiffens the sidewall of the tire and reduces chances of pinch flats or burps when run tubeless. The 20mm Apex is more than 60% taller than traditional apex inserts. Increased stiffness, fewer pinch flats or tires bottoming out on the rimwall, and the ability to ride at lower pressures equals improved control and grip when cornering. The added stiffness also helps translate feedback to the rider so they can tell what is happening at each contact point. This feedback allows the rider to know exactly how hard to push it before the tires break loose.
New Compound – RSR dual layer
Kenda has also developed a new compound for these new gravity tires – an evolution of the existing Race Stick-E Rubber (RSR) compound. Building on the original, the new RSR compound is a dual layer tread rubber, with the soft RSR compound on top and the stiff SRC on bottom. This new dual layer compound offers better performance because the stiff bottom SRC layer serves as the hard foundation for the softer RSR layer to push against. The result is a compound that provides better control and lasts longer than previous versions.
Hellkat – fast rolling intermediate gravity tire
The Hellkat Pro is an all-new downhill racing tire, developed with professionals on the UR Team racing with decades of experience on the World Cup circuit. The Hellkat Pro is characterized by superior braking control and cornering traction, without sacrificing rolling resistance performance. Additional emphasis has been placed on the overall weight of the tire, the elimination of punctures and casing fractures, and construction all to yield the best results when run tubeless. The tread design is optimized for maximum performance characteristics across a wide range of conditions by balancing traction, handling and rolling speed. It has superior grip and slow rebound with super low rolling resistance because of the new dual layer tread rubber. The KVS increases cut resistance on sidewall, ICB a lightweight belt under the tread increases the puncture resistance.
Hellkat K1201- knob characteristics – tread blocks
Hellkat K1201- knob characteristics – shoulder knob
Helldiver – versatile, fast & lightweight gravity tire for dry condition
The Helldiver is a modern take on the fast rolling, dry condition gravity tire with aggressive side knobs. Versatile, quick, and lightweight with great grip when cornering. Developed in conjunction with Kenda engineering teams in Taiwan and North America along with cooperation with the UCI World Cup downhill racing UR Team. In development the key challenge was to make the tire fast rolling without sacrificing grip and braking traction.
This was accomplished with the use of the dual layer RSR compound and the siped center knobs that provided braking traction when needed and does not adversely affect rolling resistance. However, not every knob is siped because siping generally increases rolling resistance. The tread design is optimized for hard-pack race courses balancing the traction, handling and rolling speed requirements. It ́s as fast as a semi slick but with superior braking traction and cornering grip for its category.
Helldiver K1202- knob characteristics – tread blocks
Helldiver K1202- knob characteristics – shoulder blocks
This article is part of Mtbr’s coverage of the 2017 Sea Otter Classic in Monterey, California. For more from Sea Otter CLICK HERE.