Adding the Bearing Spacer Upgrade Kit to M1 rear hubs dramatically improves bearing durability and eliminates hub play associated with an unthreading preload adjuster. The Bearing Spacer Kit can be installed by retailers or competent home mechanics. Please note: All parts of the update kit need to be used together for the kit to work.

• M1 BEARING SPACER / BEARING KIT - Part# 8004010(need one per rear hub)
• BEARING DRIFT KIT 15 M1 BEARING SPACER - Part# 8004015 (This is the tool kit. Shops need just one of these).