Step 1

Remove the blue air cap and cover the air valve with a rag as you release the air pressure.

Step 2

With a chamfer-less 6-point 26mm socket (PN: 398-00-602), unthread the topcap assembly completely (counter-clockwise). Pull straight up to remove the entire topcap assembly from the left side upper tube. Some upward force might be needed to overcome the friction of the stock air volume spacer.

Step 3

Use a 2mm hex wrench to unthread the set screw in the red rebound knob. Remove the knob and set it aside. 

Step 4

Use a 10mm socket to unthread and remove the air side bottom nut. Remove and discard the original crushwasher.

Note: You may need a custom 10mm socket that has been reduced in outer diameter to clear certain Step-Cast lower leg castings. 

Step 5

32mm: Use a 10mm socket to remove the damper side bottom nut. Remove and discard the original crushwasher.

Note: You may need a custom 10mm socket that has been reduced in outer diameter to clear certain Step-Cast lower leg castings. 

34mm: Use a 15mm socket to remove the damper side bottom nut. Make sure to remove and discard the orginal crushwasher which may be stuck to the bottom nut.

Step 6

Use Damper Removal Tools 398-00-681 and 398-00-682 to dislodge the shafts from the lowers. Make sure that you have approximately half of the available threads engaged with your tool before striking with your mallet. Remove the damper removal tools, then bring the fork upright over an oil basin to drain. After oil stops draining from the lowers, pull the lowers off of the upper tubes and set them aside.

Step 7

Remove the retaining ring from the bottom of the air side upper tube. 32mm forks use a double wound flat retaining ring. 34mm forks use a single wound Hoopster style retaining ring.

Step 8

Thread the damper removal tool (PN: 398-00-681) onto the air shaft and pull out from the upper tube to remove the air shaft assembly.

Step 9

Apply a thin film of Slick Honey to the inside of the upper tube. Apply a thick film of Slick Honey to the new air shaft assembly in the areas of the piston, neg plate, and shaft above the neg plate. 

Step 10

Insert the air shaft assembly into the end of the upper tube. Push the air shaft assembly into the upper tube far enough to allow you to start the neg plate into the upper tube. Push the shaft into the upper tube to pull the neg plate into its installed position.

Step 11

Replace the retaining ring making sure it is fully seated in its groove by pulling on the air shaft. (32mm version shown)

Step 12

Inject 3cc of FOX 20wt. Gold oil into the main air chamber through the top of the upper tube. Reinstall the topcap into the fork crown and tighten clockwise to 220 in-lb (24.8 Nm) torque with your 6-point chamfer-less 26mm socket.

Step 13

Add air pressure to your desired setting using a FOX high pressure pump. See the Setting Fork Air Pressure section for more information. Reinstall the blue air cap.

Step 14

Install the Lower Leg Assembly onto the upper tubes. Inject the approprate amount of FOX 20wt. Gold oil into each leg through the bottom hole.

Step 15

Install a new crushwasher on each side followed by the appropriate bottom nut. Torque both bottom nuts to 50in-lb (5.7 Nm). 

Step 16

Use a 2mm hex wrench to install the red rebound knob. Make sure that the set screw lines up with the depression in the rebound adjuster shaft. Clean the exterior of your fork.

Step 17

After assembly you must compress the fork 3-5mm very slowly until you feel the chamber pressures equalize.