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General Instructions
  • Determine the steer tube cut length by determining the total stack height and leaving extra length for spacers and the possibility of installation on alternate frames.
  • Cut the steer tube with a pipe cutter. Use a file to remove all sharp edges and material protruding from the outer and inner diameter of the steer tube cut.
  • Press 1 1/8" star nut using a star nut installation tool.
  • Press headset race according to headset assembly instructions.
  • Clean all clamping surfaces prior to assembly.
  • M6 fastener torque: 5-6 N-m.
  • M6 fastener torque: 8-10 N-m.
When Changing Inserts
  1. Refer to frame compatibility page first!
  2. Leave the steer tube in the frame.
  3. Leave the lower crown clamped to the stanchions.
  4. Remove the top cap and steer tube spacers.
  5. Loosen the two M6 insert clamp screws.
  6. Loosen the M5 screws on the upper clamp only.
  7. Remove the inserts.
  8. Wipe the clamp surfaces and new inserts clean with a clean rag.
  9. Install the new inserts.
  10. Install steer tube spacers and top cap and adjust headset.
  11. Make sure the inserts are installed in the clamps completely.
  12. Make sure the steer tube is installed in the lower insert completely.
  13. Check fork alignment.
  14. Torque M6 screws to 5-6 N-m.
  15. Torque M5 screws on upper clamp to 8-10 N-m.
     Item Number Description
    1 Steer Tube
    2 Insert
    3 Upper Crown
    4 Lower Crown
    5 M5 Screw
    6 M6 Screw

    Crown Dimensions

    Rock Shox Boxxer (left), Fox 40 (right)