Rubbee X adds additional wear to the tire but nothing that should be worried about. We cast the rollers from a specially developed polyurethane compound mix which guarantees the best contact between the tire and the roller. This compound also allows us to reach phenomenal grip in wet conditions. We test roller materials for thousands of kilometers (literally!) on the same tire without drastic wear&tear. In any case it is generally recommended to change bicycle tires every 2000-3000 km so we recommend to follow this rule. Cool fact – our roller material is also used in high-end sports cars suspensions !