What goes on inside your fork and shock? Discover the whole story as we delve into the inner workings of your suspension. Paul Shepherd from Fox importer Mojo explains the role of each component…

Inside the Fox 34 FIT CTD fork

Inside the Fox 34 FIT CTD fork

Fox Float 34 with FIT cartridge

FIT cartridge

The Fox Isolated Technology (FIT) cartridge basically stops the air and oil from mixing, which would impede suspension performance

Single wall expanding bladder

The bladder gives the air and oil somewhere to go as it expands, so it reduces fluid aeration and keeps your fork feeling consistent even as it heats up

Wiper seal

Keeps the oil in and mud out

Foam ring

Saturated in Fox Float Fluid, the ring lubricates the stanchions as they move

Volume reducer top cap

An internal spacer which reduces the air volume, so the suspension gets firmer as it approaches full travel

Top-out spring

A soft buffer for the fork to fully extend against when, for example, your wheel comes off the ground.

Lower leg bushes

Oil is forced into the tall, slotted bushings during the compression stroke. When the fork cycles up and down, the oil is trapped between the bushings, upper tubes and seals to lubricate the system.

Float Fluid

Lubricates the air pistons’ seals — adding fluid also reduces the amount of air in there, so it makes the suspension slightly more progressive

Negative Spring

A long, air-negative spring makes for a more linear spring feeling fork

Inside the Fox Float X shock

Inside the Fox Float X shock

Fox Float X shock

Air volume reducer

Tinker with this to change your air spring curve. Larger spacers make the air spring rate progressive; smaller spacers make for a more linear coil-spring feel

LV air sleeve

Also called the air can, the sleeve is pressurised when you put air into the shock

Positive air chamber

Pressurised air acts as an easily adjustable spring

Negative air pressure

Pressurised air preloads the shock into its travel, so there’s less effort needed to get it moving at the start of the stroke – it basically makes the shock feel more sensitive

Air sleeve transfer port

Lets air move between the positive and negative chambers so the shock can automatically balance its spring rate

Piston assembly

Damping is created by shims that flex open, allowing oil to flow across the piston on the rebound stroke

Suspension fluid

Provides the fluid for damping and lubricates the shock internals

Body tube

Stores the fluid and houses the piston and its valves. The internal seals inside the air sleeve slide against the tube

Looking to buy a new long travel suspension fork? Check out our fork grouptest.

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