BFGoodrich ST565

Steer-optimised rib pattern. A five-rib, straight-groove layout with high-density lateral siping stabilises the contact patch for the BFGoodrich ST565, delivering precise on-centre tracking and minimising river wear under long-haul steer-axle loads. The optimised positive-to-void ratio equalises footprint pressure to resist cupping and feathering, while variable pitch sequencing lowers pattern noise for driver comfort. Wide primary circumferential channels accelerate water evacuation to maintain wet-lane discipline in heavy rain, supporting consistent steering torque and reduced stopping distances. Tie-bars across intermediate ribs control block movement under lateral scrub typical of tight depot manoeuvres, extending usable tread life and preserving casing integrity for retread.

Low-hysteresis tread compound. A silica-reinforced, low-hysteresis polymer network in the BFGoodrich ST565 reduces internal energy losses at the tread-ground interface, lowering rolling resistance without sacrificing chip-cut resistance on coarse New Zealand chipseal. Heat-stable elastomers and optimised carbon black dispersion limit thermo-oxidative degradation at sustained motorway speeds, keeping crown temperatures in the optimal window for durability and fuel efficiency. The compound’s tailored glass transition temperature maintains modulus in cold, wet conditions, improving micro-scale adhesion on polished surfaces while resisting tearing during high-scrub urban turns. The result is reduced fuel burn per kilometre and a longer wear horizon, supporting total cost of ownership targets for fleets.

Reinforced decoupling shoulder. A robust shoulder architecture with a decoupling groove and graduated stiffness profile manages edge stress concentrations that typically drive irregular shoulder wear on steer tyres. Reinforced shoulder ribs with under-tread wedges and chamfered groove edges distribute shear forces during tight cornering, mitigating rib tearing and scalloping on high-scrub routes. This geometry helps the BFGoodrich ST565 maintain a square, even footprint across the wear life, delaying the onset of outer-rib step wear and preserving wet-grip channels. Better wear uniformity translates into longer removal mileage and cleaner casings for multiple retread cycles.

Stone-ejecting groove geometry. Tapered main grooves with stepped bases and integrated stone-ejector ridges are engineered to shed embedded stones before they drill into the belt package, a key advantage on coarse aggregate surfaces common across New Zealand. By disrupting the helix path of trapped stones, the BFGoodrich ST565 reduces penetrations at belt edges, lowering the risk of rust jacking and ply separations. The groove wall angles enhance self-cleaning at highway speeds while maintaining lateral stiffness for precise steering. Protecting the crown from stone drilling improves uptime and preserves retreadability by keeping the casing free from puncture-initiated damage.

Heavy-duty steel casing. A high-tensile steel belt package with optimised cord angles sits over a robust body ply and reinforced bead apex to resist deformation under steer-axle loads, heat, and repeated braking cycles. Belt-edge gum strips and a cool-running undertread help dissipate heat away from the shoulders, reducing interply shear and inhibiting separations over long duty cycles. The bead bundle and chafer design improve clamping force and abrasion resistance on the rim seat, supporting stable handling and minimising slip in high-torque manoeuvres. This durable casing architecture in the BFGoodrich ST565 is engineered for multiple, high-quality retreads, maximising lifecycle value for fleet operators.