kyb plastic ics piston question

I have a set of 12 kx 450 kyb forks. I have heard and read it could be common for the plastic ics pistons breaking. Is there any symtoms to this happening or do you just have to take apart and check them?

Symptoms are minimal compression and rebound damping due to cavitation in the cart.

I guess the first thing you might notice is a topping out sensation any time the wheel comes off the ground.  If you take the forks off the bike it should be pretty obvious if one or both are still working correctly, and it might only be one or the other.  There would be very little if any damping in either direction at the top of the stroke.

You should take them apart anyway. At least fresh oil. Inspect for wear. Inspect shim stacks for damage. Drill the plastic free pistons if not done already. Replace them if cracked.

I thought the kx free piston was vented compared to the yz. Been a while since I've seen them. I've only seen kx piston fail when someone disables the mid speed damping. 

all of the ones that have come into the shop that were cracked, broke or shattered, the owners didn't feel any thing wrong. Pull apart and replace with metal ones or drill hole in one side of the piston if its still good.

thanks guys.

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