Learn More about the FOX Factory DPS

The FOX Factory DPS is the most popular and best riding XC, down-country and light trail shock on the market. It’s external adjustments include rebound, a climb switch as well as 3 low speed compression settings. These low speed compression modes modify the shock’s performance in the “Open” mode of the climb switch. Keep reading about the FOX Factory DPS Shock details. We’ll go over volume spacing, rebound, compression and how these adjustments interact!

FOX DPS Shock Adjustments (Factory and Performance Elite)

Air Spring & Volume Spacers

The FOX DPS is adjustable with air spring as well as volume spacers. This allows proper setup for a wide rage of riders.

SAG is adjusted by PSI. Down-County or Trail riders tend to set approximately 30% sag. Those looking for a slightly more plush setup can modify setup between 25-30% and use volume spacing as well as compression to fine tune support.

Volume Spacers

Volume spacing provides fine tuning options to support the air spring.

Installing a larger volume spacer, thus reducing the air spring’s available volume, the air spring’s ramp rate is increased. This provides additional bottom out support and pop.

A smaller volume spacer creates a more linear feel, as the shock has more volume during shock compression per mm of travel. This means there is less ramp, or rise in PSI during compression.

Do not install more volume spacers than the FOX advises. Installing more than the maximum volume spacers will result in  product damage and potential for injuries, etc.

Do not install more volume spacers than the FOX advises. Installing more than the maximum volume spacers will result in  product damage and potential for injuries, etc.


Learn more about the FOX Float DPS with the FOX Tuning Guide Here (PDF opens in new tab)

FOX Float DPS 3 position Rebound Adjustment

FOX FLOAT FACTORY DPS Rebound Controls

The DPS provides a rebound control with 11 clicks of adjustment.

Heavier riders will use more rebound control than lighter riders to slow the air spring’s return to neutral.

As your ground speeds increase it is common to allow your bike to rebound more quickly to prepare for the next terrain feature and avoid suspension packing from slow rebound setup.

Fox Factory DPS Compression Open Adjust and 3 position switch

FOX Float Factory DPS Compression Controls

The Fox Float Factory DPS shock provides two controls to help fine tune compression.

First is the blue 3 position switch which adjusts from Firm, Mid and Open. Also known as a “climb switch” the use of this is dependent on rider style, preference and terrain.

Fine tuning the low speed compression can be accomplished in the Open mode by adjusting the black dial located around the circumference of the blue 3 position switch.

3 settings are available with “1” being the most plus and “3” the most firm.

FOX Factory Float DPS Rear Shock Compression Setting

Suspension Setup Concepts

Learn about suspension setup basics on the following tabs. Each tab has a video with the basics of Air Spring / PSI, Volume Spacers, Compression, Rebound (or watch it all in one place with the final tab).

Each tab has a text section with a bit more in-depth look at the typical MTB suspension settings and how they intertwine.

PSI / Spring Rate

MTB suspension must accommodate a wide range of rider weight. To achieve this nearly all forks and rear shocks use an adjustable air spring.

By varying air pressure riders set a desired sag, or percentage of travel that the bike “sits into” under neutral loading.

Modifying this sag percentage will change small bump compliance as well as bottom out characteristics.

Learning how to Pre-Charge your suspension pump will help you make finite adjustments to sag.

Typically 15% sag is for a firm setup and 20% sag is considered plush.

Air Spring Fine Tuning Control(s): Volume Spacers & Compression

Volume Spacers
Air springs ramp rate, sometimes called Spring Rate, is based on how air compresses in the containment cylinder. As the air is compressed the PSI increases according to the decreasing volume of the containment. This is done via non-compressible volume spacers in the air chamber.

Compression.
Hydraulic damping assists air spring providing support in mid-stroke and bottom out.

Opposing Control: Rebound.
Higher spring rate will drive the suspension back to neutral with more force than a lower spring rate. To keep the bike from skipping across trail rebound damping is utilized.

Volume Tuning

As suspension compresses (travel reduces) a piston moves closer to the end of a sealed container. By decreasing the volume of the container the PSI pushing back on the piston is increased.

Adding or removing non-compressible volume spacers riders modify the air spring’s ramp rate which directly changes the amount of support and bottom out feel of the fork or shock.

By removing volume spacers a rider increases the available volume in the suspension. The larger volume compresses less per mm of travel resulting in a lower PSI per mm of travel. This creates less support and is utilizes more travel.

Adding volume spacers decreases the available volume. With less air volume the PSI per mm of travel increases providing more support and greater resistance to bottom out.

Opposing Control: Rebound.
Rebound may need to be adjusted for volume tuning depending on how drastic of a PSI change is being tuned in or out of the suspension.

“Helping” Control: Compression.
Adding compression provides additional support and bottom out resistance.

Compression

Your compression controls provide damping to slow suspension travel as a load is applied and the suspension is compressed. (easy one right?)

When riders have found sag and volume spacing preferences compression controls provide minute adjustments to dial in performance. Adding compression provides more support allowing the suspension to ride taller in its travel which is important when dialing in a bike’s personality in corners, etc.

With too little compression a bike will sit deep in the travel. This compromises cornering and braking force resistance. Headtube angle, bottom bracket height, front to rear weight bias, etc are modified as a bike goes through its travel. Maintaining control of the use of travel is paramount for good performance.

Since compression hydraulically slows the suspension’s use of travel it therefor lowers the air spring’s PSI. Properly setting compression controls will help ease the load on the rebound system by controlling the air spring’s push back onto the rebound circuit.

Too much compression will cause a bike to feel harsh and not use appropriate amounts of travel.

Generally, compression settings are fine tuned after sag and volume spacing have riders “in the ballpark.”

Low speed compression controls mid-stroke as well as support in cornering and against brake dive.

High speed compression helps with bottom out and high shaft speed inputs.

3 positions switches are a type of compression circuit with Open the most plush, Mid providing some additional support and Firm for climbing. If you climb in firm remember to put it back to plush for the downhill or you’re in for a potentially rough ride.

Rebound

Rebound damping controls a suspension’s shaft speed returning to a neutral position. Or, how fast the air spring pushes back as the load changes.

More rebound damping slows the suspension by decreasing the amount of fluid allowed to pass through the hydraulic design.

Less rebound damping allows the suspension to return faster with less hydraulic restriction on the damper.

Rebound setting is based on weight, ground speed, terrain and aggression. Setting the rebound properly means finding the right frequency or feel for your riding.

If your rebound is too fast, or doesn’t have enough clicks of rebound, the bike will tend to skip and suffer poor small bump compliance.

When the rebound is too slow, or you have too many clicks of rebound, the suspension may “pack up” creating a harsh ride as each bump uses progressively more travel forcing the suspension deeper into the travel, which will have higher spring rates.

Opposing: Air Spring PSI / Spring Rate.

“Helping” Control: Low & High Speed Rebound.

Some suspension is designed with 2 rebound circuits. The High Speed Rebound circuit is designed to provide additional control resisting increased PSI late in suspension travel.

Typically High Speed Rebound settings are used as the Low Speed Rebound controls edge towards closed. Example: you might not use any clicks of High Speed Rebound until you reach “X” clicks on the low speed.