Designed for years of service even in the dirtiest riding environments.
OE Spacers typically wear out within a year of hard riding. OE wheel spacers should be checked and replaced as needed with every wheel bearing change.
Water and dirt act as a grinding compound between the seal face and the mating surface of the spacer. Once the grooves are deep enough, the sealing surface is lost allowing water and dirt to pass through and contaminate the bearing.