Garage Files: Swapping Volume Spacers in Your Fox Suspension

Swapping Volume Spacers in Your Fox Suspension

Dialing in the air volume on your suspension can make a big difference in the ride. Air volume has a big effect on the progressiveness of your suspension, so adding or removing spacers will change how your suspension feels at the bottom of its travel. By adding these volume reducers, you can force your fork or shock to resist bottoming out. For aggressive riders, this is a valuable tuning option. Fortunately, Fox offers some of the most tunable pieces of suspension on the market. In this “Garage Files” we will show you how to install volume reducers in both your fork and shock.

1 Dialing in your air volume is one of the easier procedures with your suspension, but you do need a few tools. For this you will need a ratchet, Fox Fluid, socket fittings for the air spring, volume spacers and, in some cases, a strap wrench.

2 Start by spraying isopropyl alcohol around the air-spring cap to make sure the area is clean from any contaminants.

3 Unthread the air-spring cap and attach a shock pump to release all of the air pressure in the fork. Before releasing the air, record your current air pressures so you can duplicate them after the volume spacers are installed.

4 Fox offers socket fittings in a few different sizes. For the Float 34 we will need the 28-millimeter non-chamfered fitting.

5 Carefully align the socket on the air-spring cap and begin to unthread it. It will take a little force to break the threads loose.

6 Once the air spring is unthreaded, pull the cover off. Most bikes come with reducers installed from the factory.

7 In this case we want to make our fork more progressive (resist bottoming out). To achieve this, we will add one volume reducer. One spacer makes a big difference in the progressiveness.

8 Reinstall the air-spring cover and begin tightening it down by hand before using the 28-millimeter socket fitting.

9 Use the ratchet to tighten the top cap down all the way. The top cap should be torqued to 24.8 newton meters, which is tighter than you can get with your fingers, but not as tight as you could go with a ratchet.

10 With the air spring threaded properly and back into place, put the desired air pressure back into the fork and reinstall the valve cover.

11 Now, we’re going to work with the rear shock. The process is very similar and can usually be done with the shock still on the bike. Clean the air can with isopropyl alcohol to make sure no contaminants will get inside.

12 Record your air pressure, then release the air completely. Make sure all air is out before you begin unthreading the air can.

13 Unthread the air sleeve. If it’s too tight, you may need a strap wrench to loosen it. The air can will unthread counterclockwise.

14 With the air can unthreaded, pull it down all the way to the end of the shaft body. You might feel a little resistance from the seals. Slide the bottom-out bumper and plate away from the eyelet assembly. You can use your fingers or blunt-ended tool that won’t scratch the surface of any of the parts.

15 Take the supplied Float Fluid from the tuning kit and apply a few drops to the spacer.

16 Take the desired volume reducer and press it into the eyelet until you feel it snap into place.

17 Slide the bottom-out damper and push it back into place.

18 Slide the air can back up and thread it back on until it is hand-tight.

19 Slide the O-ring back into place.

20 Open up the rebound all the way and then put pressure back into the shock. Cycle through a few times to properly equalize the system, then re-check the pressure. You may have to add a few more psi.

21 Reinstall the valve cover and go hit the trails.


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