Styres

Styres, commonly written tyres in British English and tires in American English, are circular rubber components that fit around wheels to enable contact with the road. They provide traction, support vehicle weight, absorb shocks, and transmit steering, braking, and acceleration forces.

Most modern tyres are tubeless and use radial construction. A tyre consists of the inner liner, a carcass of fabric cords, belts often of steel or synthetic fibers, and the tread and sidewalls. The air inside an inflated tyre supports the vehicle and maintains shape; the pressure is critical for performance and safety. Tyres come in various sizes and load and speed ratings.

Types include summer tires optimized for warm conditions; winter tires with special rubber compounds and tread patterns for cold, snow, and ice; all-season tires that aim to perform in a range of conditions; and specialized variants such as run-flat tyres and off-road tyres. Tread patterns may be symmetric, asymmetric, or directional, affecting water evacuation, grip, and noise.

Regulatory and safety aspects: in many regions tyres have speed ratings and load indices; performance is tracked by standards such as UTQG in the United States and ECE under European regulations. Tire aging is a concern; most manufacturers recommend replacement after about six to ten years, independent of tread wear, due to rubber hardening and structural degradation. Routine maintenance includes keeping correct inflation, regular rotation, alignment checks, balancing, and prompt repair of punctures when safe.

Environmental considerations include retreading where possible, recycling of worn tyres, and the environmental impact of component materials. Advances in compounds and tread design aim to improve fuel efficiency, wet grip, and longevity.