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Installing Your Fork | Before You Ride | Setting Sag | Adjusting Rebound | Locking Out the Fork | Adjusting Lockout Force | Adjusting Low-Speed Compression | Service Intervals | Important Safety Information


3.5 in./90 mm


low-speed compression, lockout, lockout force adjust, air spring pressure, rebound

spring/damper type

air/open bath

intended use


Installing Your Fork

Be sure your fork is properly installed before proceeding. Clicking on the link above will take you to a new page. If your fork came pre-installed on your bicycle, continue with Adjusting Rebound.

Before You Ride

  1. Check that quick-release levers are properly adjusted and tightened.
  2. Clean the outside of your fork with only mild soap and water, and wipe dry with a soft dry rag.

    Note:  Do not use any solvents or de-greasers, as these products can cause serious damage to paint and anodized parts (upper tubes, knobs, steerers).

    Do not spray water directly on the seal/upper tube junction. Do not use a high pressure washer on your fork.

  3. Inspect entire exterior of fork for damage. The fork should not be used if any of the exterior parts appear to be damaged. Please contact your local dealer or FOX for further inspection and repair.
  4. Check headset adjustment. If loose, adjust according to manufacturer’s recommendations.
  5. Check that brake cables or hoses are properly fastened.
  6. Check that the front and rear brakes operate properly on flat land.

Setting Sag

To get the best performance from your fork, it is necessary to set and adjust sag. Generally, sag should be set to 15 – 25% of total fork travel.

  1. Unscrew the blue aircap (shown below) on top of the left fork leg to expose the Schrader valve.  

  1. Attach a FOX Racing Shox High Pressure Pump to the Schrader valve.
  2. Using the Air Spring Settings table below, pump your fork to the appropriate setting using the FOX High Pressure Pump, then remove the pump.
  3. Install a zip tie with light friction on the upper tube and push it down until it contacts the fork seal.
  4. Carefully sit on the bike and assume a normal riding position. The fork should compress slightly.
  5. Being careful not to further compress the fork, dismount the bicycle. Measure the distance between the seal and the zip tie. This distance is sag.
  6. Compare your sag measurement to the Sag Setup table below.

    If your sag is lower than on the table
    , screw on the pump fitting, note the current air pressure setting and depress the black bleed-valve to reduce the gauge pressure by 5 psi. Measure sag again and repeat adjustment, if necessary.

    If your sag is higher than on the table
    , screw on the pump fitting, note the current air pressure setting and pump to increase the gauge pressure by 5 psi. Measure sag again and repeat adjustment if necessary.
  7. Screw the blue aircap back on, and go ride.

    Air Spring Setting Guidelines

    Rider Weight

    Air Pressure

    < 125 lbs.

    45 psi

    125 - 135 lbs.

    50 psi

    135 - 145 lbs.

    55 psi

    145 - 155 lbs.

    65 psi

    155 - 170 lbs.

    75 psi

    170 - 185 lbs.

    85 psi

    185 - 200 lbs.

    95 psi

    200 - 215 lbs.

    105 psi

    215 - 230 lbs

    115 psi

    230 - 250 lbs.

    125 psi

    Sag Setup


    XC/Race FIRM


    80 mm (3 1/8")

    12 mm (1/2")

    20 mm (3/4")

    100 mm (4")

    15 mm (5/8")

    25 mm (1")

    120 mm (4.7")

    18 mm (3/4")

    30 mm (1 1/4")

    Sag Troubleshooting



    Too much sag

    (+) air pressure in 5 psi increments

    Too little sag

    (-) air pressure in 5 psi increments

    Excessive bottoming

    (+) air pressure in 5 psi increments

    Harsh ride; full travel not utilized

    (-) air pressure in 5 psi increments

Adjusting Rebound

The rebound adjuster knob is located at the top of the right fork leg; see the above figure. This knob has approximately 12 clicks of adjustment.

Rebound controls the rate of speed at which the fork extends after compressing. Turning the knob clockwise slows down rebound; turning the knob counterclockwise speeds up rebound. As a starting point, turn the rebound adjuster knob all the way clockwise (full in) until it stops, then turn counterclockwise (out) 6 clicks.

Knob Setting
(clicks out from full in)

Setting Description

Tuning Tips

Setup Tips


Slow Rebound

Too slow and your fork will pack down and ride harsh.

If you increase your spring rate or air pressure, you will need to slow down your rebound


(Factory setting)

Average Rebound



Fast Rebound

Too fast and you will experience poor traction and wheel hop.

If you decrease your spring rate or air pressure, you will need to speed up your rebound setting.

Locking Out the Fork

The blue compression lockout lever is located just below the black lockout force adjuster knob (see "Adjusting Lockout Force" below). It allows the rider to close the compression damping circuit in the fork. This keeps the fork at the top of its travel, making it harder to compress.

Rotate the lever fully clockwise to lockout the fork. This position is useful in climbing and sprinting situations, but will sag with the rider’s weight. The fork will "blowoff" in the event that a big hit is encountered with the fork locked out.

To unlock the fork, simply rotate the lever fully counterclockwise.

Note:  The fork may cycle a couple of times after enabling lockout. Once complete lockout is achieved, the fork may continue to move 3 - 5 mm. This is normal and does not affect performance.

Adjusting Lockout Force

Even when your fork is fully locked out, there are instances when you still want your fork to be active. To protect your fork's internal parts, your FOX fork will "blowoff" when it encounters an intense hit. You can adjust when the fork blows off—lockout force—by adjusting the knob located on the underside of the right fork leg, next to the dropout.

A convenient tuning feature of the lockout force knob is that it allows you to leave your fork in the locked out position—no more fiddling with fork controls when the trail requires your undivided attention. Although you might need to adjust the knob a few times to find the sweet spot, once it is found you can simply leave your fork locked out. Your fork will then respond to hits in the trail (greater lockout force), for example, but will be locked out (lower lockout force) when you are out of your saddle on a climb.

Turn the knob clockwise to increase lockout force and counterclockwise to decrease lockout force.

There are 10 clicks of adjustment. As a starting point, turn the knob all the way clockwise until it stops, then back off one click counterclockwise.

Adjusting Low-Speed Compression

Low-speed compression damping is adjusted with the blue bezel ring that is positioned just below the blue lockout lever (see the figure above). This ring has approximately 9 clicks of adjustment. Compression damping controls the fork compression speed. Adjust the low-speed compression with lockout disabled (lockout lever fully counterclockwise). As a starting point, turn the low-speed compression bezel ring all the way counterclockwise (full out) until it stops, then turn clockwise (in) 5 clicks.

Knob Setting
(clicks in from full OUT)

Setting Description

Tuning Tips

Setup Tips


Soft Compression

Too soft and your fork will pack down and ride harsh.

Maximum wheel traction and bump compliance. Too soft and you maybe have excessive brake dive and wallowy feel.

(Factory setting)

Average Compression



Firm Compression

Too firm and you will experience poor traction and wheel hop.

Resists brake dive and keeps the fork up in the travel. Too firm and you may have poor traction in loose conditions.  

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