If the X was revolutionary in tyre terms, the XAS was the next great leap forward for Michelin. Michelin boffins worked out that different areas of the tyre have entirely different roles, so designed the XAS to reflect this. 

The result is a tyre with much-improved stability, grip and road holding and it has one of the best-looking tread patterns you can buy. There are twelve sizes in the XAS range with some sizes having a FF (Formula France) version with a softer, grippier compound.