How to Remove the Bearings From a Stumpjumper FSR

The Stumpjumper FSR is a mountain bike made by the Specialized Bicycle Company. Like most modern bicycles, the Stumpjumper FSR has a cartridge bearing as opposed to bearings separate from the axle spindle. In the cartridge bearing assembly, the bearings and the spindle are combined in one unit that is inserted into the bicycle’s bottom bracket and is held in place by two lock rings. The cartridge bearing system eliminates the need for frequent lubrication and can be removed with a few of the proper tools.

Things You'll Need

  • Crescent wrench
  • 8 mm Allen wrench
  • 16 mm wrench
  • Crank arm puller tool
  • Lock ring tool
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Instructions

    • 1

      Take off the bicycle chain from its sprocket and let it hang below the bottom bracket. Shifting the derailleur down to the lowest front gear will simplify this process.

    • 2

      Remove the bolt on the crank arm with an 8 mm Allen wrench.

    • 3

      Insert the crank arm puller tool into the crank arm threads and thread the outer threads of the crank arm puller in the crank arm. Rotate the internal driver in the crank arm puller tool clockwise until the puller meets the crank arm.

    • 4

      Clamp a crescent wrench on the outside of the puller tool, holding it still. Grab the internal driver in the puller tool with a 16 mm wrench. Rotate the 16 mm wrench clockwise, pushing the internal driver inward and loosing the crank arm from the bearing cartridge.

    • 5

      Repeat this process on the other crank arm.

    • 6

      Place the lock ring tool into the right drive-side of the lock ring that holds the bearing cartridge within the bottom bracket.

    • 7

      Clamp the crescent wrench onto the lock ring tool, rotating it clockwise to loosen the ring. Remove the tools and unthread the ring with your fingers. Take the lock ring off.

    • 8

      Unthread the lock ring on the left, non-drive side of the bicycle with your fingers, this time rotating the ring counter-clockwise. Take out the lock ring. The bearing cartridge is now free and can be removed from the bottom bracket.