What does 98W mean on UK car tyres? Tyre load index and speed rating explained

98W on UK car tyres indicates a load index of 98 (750kg per tyre) and a W speed rating (270km/h maximum). The load index shows the maximum weight each tyre can carry, while the speed rating indicates the tyre's top safe speed under load conditions. For example, popular UK models like the BMW 3 Series or Vauxhall Corsa typically use tyres with lower speed ratings (like V for 240km/h) as they don't require such high performance. Tyres support your vehicle's weight, provide traction for acceleration/braking, absorb road shocks, and ensure safe handling - making correct specification crucial for UK MOT compliance and insurance validity.