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Air Spring Compression Ratios: 2013 FLOAT CTD

Note:  Air spring volume spacers for 2013 FLOAT CTD rear shocks are easily installed after releasing all air pressure and removing the shock air sleeve. The spacers offer a quick and easy means to adjust your shock's air spring compression ratio.

PN Description
803-00-802 Kit: FLOAT CTD 9 mm Shaft, Air Spring Volume Tuning Kit


Volume Air Spacer Configurations

Note:  The green fields in the table identify the combinations of length, travel, and eyelet with volume spacer size that offer the most linear compression ramping curve. The light orange fields in the table identify the combinations that simply cannot be installed.

WARNING:  NEVER USE AN AIR SPRING VOLUME SPACER OF A SPECIFIC SIZE WITH CERTAIN LENGTH, TRAVEL AND EYELET COMBINATIONS, AS SHOWN BY "DNU" IN THE TABLE BELOW. With these combinations, the resulting compression ratio goes beyond the bounds of safe product usability. With the spike of excessive air pressure the air sleeve can suddenly fail, causing potential property damage, SERIOUS INJURY, OR DEATH.

  = Usable   = Most Linear Curve CBU = Cannot Be Used DNU = DO NOT USE!

Length Travel Eyelet No Spacer 0.20"^3 0.40"^3 0.60"^3 0.80"^3 0.92"^3
5.500 1.000 SV 2.3 2.6 2.9 3.5 CBU CBU
6.000 1.250 SV 2.7 3.0 3.4 DNU CBU CBU
6.500 1.500 SV 3.0 3.4 3.9 DNU CBU CBU
6.500 1.500 XV1 2.4 2.6 2.8 3.2 CBU CBU
6.500 1.500 LV DNU DNU 2.3 2.4 2.6 2.7
7.250 1.750 SV 2.9 3.1 3.5 4.0 CBU CBU
7.250 1.750 XV1 2.3 2.5 2.6 2.9 CBU CBU
7.250 1.750 LV DNU DNU 2.3 2.4 2.5 2.6
7.500 2.000 SV 3.6 DNU DNU DNU CBU CBU
7.500 2.000 XV1 2.8 3.0 3.3 3.6 CBU CBU
7.500 2.000 XV2 2.3 2.5 2.6 2.8 CBU CBU
7.500 2.000 LV 2.4 2.5 2.7 2.9 3.1 3.3
7.875 2.000 SV 3.1 3.4 DNU DNU CBU CBU
7.850 2.000 XV1 2.5 2.6 2.8 3.0 CBU CBU
7.850 2.000 XV2 DNU 2.3 2.4 2.5 CBU CBU
7.850 2.000 LV 2.2 2.3 2.4 2.6 2.8 2.9
7.850 2.250 SV 4.0 DNU DNU DNU CBU CBU
7.875 2.250 XV1 3.0 3.2 3.5 4.0 CBU CBU
7.875 2.250 XV2 2.5 2.6 2.8 3.0 CBU CBU
7.875 2.250 LV 2.6 2.7 2.9 3.1 3.4 3.5
8.500 2.500 XV1 2.9 3.1 3.4 3.7 CBU CBU
8.500 2.500 XV2 2.6 2.7 2.9 3.1 CBU CBU
8.500 2.500 LV 2.7 2.9 3.1 3.3 3.6 3.8

Installing FLOAT CTD Air Spring Spacers

  1. Completely release the air from the shock.

  2. Clamp the shock in a soft-jawed vise. Unthread and remove the air sleeve, and wipe clean. Don't lose your sag indicator ring, if you have one.

  3. Using your fingertips, slide the bottom-out bumper and plate away from the eyelet assembly, towards the seal head.

  4. Insert the air volume spacer into the eyelet assembly.

    CAUTION:  Be sure the counterbore face of the air spacer is facing up towards the seal head. If the volume spacer is incorrectly installed, shock travel can be reduced and bottom-out loads to the eyelet can spike beyond the limits of safety.


  5. Firmly press the air volume spacer into the eyelet assembly until it snaps into place.

  6. Slide the bottom-out bumper and plate down to the air volume spacer.

  7. Apply a light coating of float fluid to the air sleeve seal and its threads.

  8. After pushing the air sleeve onto its seal part way, add about two (~2) cc of float fluid.

  9. Adjust the compression all the way open by setting the CTD lever to the descend position, and adjust the rebound all the way closed. Pressing firmly, thread in and hand-tighten the air sleeve into the eyelet assembly. Return the compression and rebound back to their original settings, install the travel indicator o-ring, wipe the shock clean with a shop towel, and you are done.

Swapping Air Spring Spacers

Note:  Use the following procedure to switch from one air spacer to another.

  1. With the air sleeve removed, slide the bottom-out bumper and plate away from the eyelet assembly towards the seal head.

  2. Using a blunt-ended hand tool (a 4 mm hex key wrench works well), gently pry and remove the original air volume space from the eyelet assembly.

    CAUTION:  Do not use any sharp tools that might damage the air volume spacer or other parts.


  3. Install the replacement air volume spacer, snapping it into the eyelet assembly.

  4. Slide the bottom-out bumper and plate down to the replacement air volume spacer, making sure the plate is evenly flush with the spacer.


  5. Return to step 7 in the "Air Spring Compression Ratios: 2013 FLOAT CTD" procedure, continuing through to its completion.


use proper tools, supplies & kits · read all warnings · know oil volumes and inspection guidelines · know disc brake specifics for all Fox forks · know air shaft travel specifics for FLOAT and F-Series forks · use correct fork torque specifications


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