Tyres are in constant development and a company that never lags behind are Avon motorycle tyres. An area of significant investment and development is the Sport-Touring tyre since the rider of today demands grip, comfort and long-life from his tyres. Well that's what the X-M stands for in the new Avon Storm 3D, extended Mileage. Many great reviews on this particular tyre. A British Tyre for British roads. The range of sizes will also suprise you as some of the sizes previously available in the Azaro ST range are now here.