There’s a good number of sleds out now that have the FOX FLOAT Airshox on the front suspension. While they have proven to be light and durable, they do require service and inspection.
One of the main benefits of this shock design is the ability to vary the airspring pressure with the use of a hand pump. The air pressure of each shock should be checked on a monthly basis through the winter. When you check the air pressure, you MUST do so with the front of the sled off the ground (the shock must be in an unloaded condition with no pressure being applied). Failure to unload the front suspension will lead to an incorrectly high pressure reading due to the shock being compressed.
Most of the FLOATs are shipped with 70 psi of air in them; their operating range is 50-150 psi. Changes should be made in 5 psi increments, with testing performed at each change to determine the result.
Remember that by attaching the air pump, it will take about 3-4 psi to fill the chamber in the pump and gauge so the shock will read this much lower than what it was really operating at. For example, you attach the pump and gauge to the shock and read 57 psi. This means you had about 60 psi in the shock to begin with.
If it was too soft (too much or frequent bottoming), pump it up to read 65 psi (you won’t lose any air when disconnecting the pump). If it was too firm (excessive harshness and suspension never bottoms out), reduce the pressure to read 55 psi (for the 5 psi change target) and try it.
It is best to set the shock air pressure at the temperature the unit will be operated at, or as close as possible. Ideally. If not, realize that a 50 degree change in temperature will change the air pressure by about 5 psi, and a 100 degree tremperature swing will amount to about a 10 psi swing in air pressure. If you set the shock to 60 psi in an 80 degree shop that the sled has been sitting in all day, it will be operating at about 50 psi when used at -20. Keep this in mind, the temperature swing can be enough to render your 5 psi change useless.
After each season, the outer air sleeve and seals should be cleaned. This service is safe for sled owners to perform, as long as they understand the high-pressure nature of the inner shock body and do not attempt to open it, or the pressure valve on the inner shock body. The internals of the shock should be rebuilt by a trained technician every 3,000 to 5,000 miles.
As for the air sleeve yearly service, a person of average mechanical ability should be able to handle it. No special tools are required, and detailed instructions to do so are included in the FLOAT owner’s manual (that comes with every sled so-equipped).