Installing Your Shock | General Maintenance | Before You Ride | Measuring Sag | Setting Sag | Adjusting Rebound | ProPedal: Dial or Switch | Boost Valve | Service Intervals | Important Safety Information | Stuck Down Shock | Air Sleeve Maintenance | DHX Air Explained
If you are installing your shock on a bike in which the shock is not original equipment:
There may be a small amount of air sleeve lubricant residue on the body. This is normal. If this residual air sleeve lubricant is not present, this is an indication that the air sleeve should be re-lubricated. Some other things to consider for all shock models:
You can also view a Flash video on Setting Sag.
To set sag on your DHX Air 4.0:
Shock Travel |
Recommended Sag |
2.00/50.8 |
.50/12.7 |
2.25/57.2 |
.56/14.2 |
2.50/63.5 |
.62/15.7 |
3.00/76.2 |
.75/19.0 |
Rebound controls the rate at which your shock returns after it has been compressed. The proper rebound setting is a personal preference, and changes with rider weight, riding style and conditions. A rule of thumb is that rebound should be as fast as possible without kicking back and pushing the rider off the saddle.
The rebound dial has approximately 22 clicks of adjustment.
For slower rebound, turn the red adjuster knob clockwise.
For faster rebound, turn the red adjuster knob counterclockwise.
The ProPedal adjustment knob allows the rider to adjust the amount of ProPedal damping. ProPedal damping affects the initial part of the compression stroke and is designed to control pedal-induced suspension bob. Since suspension designs vary, not all bicycles require the same degree of ProPedal damping.
There are 15 clicks of adjustment.
For lighter ProPedal damping, rotate the ProPedal knob (shown below) counterclockwise.
For increased ProPedal damping, rotate the ProPedal knob clockwise.
The ProPedal adjustment switch allows the rider to adjust the amount of ProPedal damping using a 2-position switch, which varies from FIRM to SOFT. ProPedal damping affects the initial part of the compression stroke and is designed to control pedal-induced suspension bob.
The switch has two (2) positions:
For more ProPedal damping, rotate the ProPedal switch clockwise.
For lighter ProPedal damping, rotate the ProPedal switch (shown below) counterclockwise.
The Boost Valve creates a position-sensitive damping scheme that allows
for a seamless transition from efficient ProPedal to square-edge bump
absorption to a bottomless end-of-stroke feel. The Boost Valve also decouples
the ProPedal and the factory-set bottom-out resistance, enabling ProPedal
adjustments to be made without affecting the
The Boost Valve is not adjusted directly. Instead, its behavior and performance characteristics are influenced by the air pressure setting in the reservoir and by adjusting the ProPedal knob.
To change the compression damping characteristics of your DHX Air 4.0 shock, attach a FOX High Pressure Pump to the air valve on the reservoir:
For a firmer ride, add 10 - 15 pounds of air pressure (to a maximum of 200 PSI).
For a softer ride, decrease the shock's air pressure 10 - 15 pounds by using the pump's bleed valve (to a minimum of 120 PSI).
Ride your bike and verify the settings before repeating the procedure.
Never ride your bike with more than 200 PSI or less than
125 PSI in the reservoir air chamber.
Doing so can damage your shock and require repairs that are NOT covered
under warranty.
Certain aspects of the Boost Valve can influence the ProPedal adjustment.
If the ProPedal adjustment knob is fully counterclockwise (lightest ProPedal damping position) and the compression damping is still too strong, attach a shock pump to the Schrader valve on the reservoir and reduce the pressure 10 - 15 psi. Repeat to achieve the desired compression damping.
If there is not enough compression damping with the ProPedal knob fully clockwise, add 10 - 15 psi to the Boost Valve until desired compression damping is achieved.
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