RockShox ZEB A1+ Air Spring Assembly Upgrade Kit

This kit is compatible with 2021 and newer ZEB models, including the ZEB R (A1), Select (A1/A2), and Ultimate (A1-A3) versions, as well as the Zeb Ultimate Flight Attendant (A3). Always verify your specific fork's model year and chassis designation before purchasing to ensure a proper fit.

ButterCups are small rubber pucks housed in the lower end of the damper and air spring shafts. They are designed to absorb high-frequency trail chatter and small vibrations before they reach your hands, significantly reducing rider fatigue on long, rough descents.

By increasing air volume, this assembly makes the initial part of the stroke more supple, improving small bump sensitivity. Simultaneously, it helps the fork sit higher in its travel, which prevents the front end from diving during steep sections and keeps your geometry more stable.

If you are comfortable performing a standard lower-leg service on your fork, you can likely handle this installation. It requires basic suspension tools, including a torque wrench and the correct fork oil, but if you are unfamiliar with internal suspension maintenance, a professional shop installation is recommended to ensure everything is seated correctly.

This specific assembly is designed for a 160mm travel configuration. While it optimizes the performance of that travel, it is not intended to increase or decrease your fork's total travel length; you should stick to the travel specification your fork was originally designed for.