Air suction sensation from rear shock

[T.A.]

I never noticed this or it’s new, but I am getting this suction sound from my rear air shock.

Is this normal or what is causing this ?

Rear air shock suction sensation

• T.A.
• Oct 14, 2019

 

[GrandPaBrogan]

Most air shocks have two air chambers. The main positive chamber pressure is what props-up your bike. When you pump air into your shock that's where it goes. The negative chamber has pressure to help initiate movement at the beginning of the stroke to make it plush... it automatically gets the appropriate pressure from the positive chamber by way of small passages or valves. If I were to make a guess, that sound may be caused by a malfunction in the negative pressure circuit.

One of my bikes has an X-Fusion rear shock too (02ProRL) and it's silent during compression and it makes the normal sound of hydraulic rebound damping on the return stroke (oil passing through a jet).

How long have you had that shock unit? Has it been doing it since brand new?

If not covered by warranty, you may have to take it to a shop where the mechanic is experienced with air shock repairs. Check for repair costs first... might be more than the price of a new replacement shock.

 

[outerlimits]

If air was to get stuck in the negative chamber it would pull or suck the shock into its travel at rest.
Sounds like you are hearing oil flow through the compression and rebound circuits. Either you have a heap of compression and rebound dialled on. Or more likely the shock is due for a service as the oil is old and full of air and cavitating as it passes through the oil circuits.