[Closed] Wheezing RP23

I have a float on a trance that makes a funny noise on rebounding from a biggish compression - honestly sounds like somebody going "woo" quickly.

I like to imagine it's the crowd

(I suppose it's cavitation or something similarly terminal, but I like it)

thing is my has been serviced recently, so hopefully nothing terminal, but hopefully a small group of gnomes with asthma.

My RP23 makes the same wheezing sound on a quick, significant compression. LBS mech says it is normal and it's been doing it for 3 years and still works fine, so assuming he is right.

thanks busydog, that's puts my mind at ease

Kasthma coat rp23?

remember AMPhysema ?

my RP3 makes a vvvvvvvvmmmmmmm noise on fast compression and it is new, did wonder about it myself as my Float R didn't do it. not worrying anyway.

Mine makes a funny squelchy pffffffft noise.

My rp2 makes a squelch for the first part of the travel, but cant hear it when riding.

Squelchy noises is cavitation & means you ain't really getting the best out of the shock, to put it bluntly.
Bout £140 to sort it at Mojo IIR.

Squelching doesnt always mean cavitation.

If the rebound is working fine then it is not calvitated.... Set the rebound slow then compress as much as you can and see how it rebounds. If it rebounds fast, or slow then suddenly fast, you have cavitation (air in the damper unit).

mine squelched from brand new, don't worry about it.

I get stereo wheeze from my Fox forks and Float R shock - and sometimes I join in too!

Think mine is screwed, let all the air out of it and I still cant compress it... back to TFT then...

Wheezing is a pretty good description, my Pushed RP23 was making expensive grinding metal on metal noises though the visible part of the piston shaft is unmarked...

Squelching doesnt always mean cavitation.

If the rebound is working fine then it is not calvitated.... Set the rebound slow then compress as much as you can and see how it rebounds. If it rebounds fast, or slow then suddenly fast, you have cavitation (air in the damper unit)

Pedantic, but that's not cavitiation.

Cavitiation isn't "air in the damper" it's the formation of vapour spaces caused by the drop in pressure accross the damping piston. To create them you need to drop the presure below the vapoour pressure of the liquid. Obviously oil boils at ~200degC at atmospheric conditions and probably still way above normal temepratures even at full vacuum so it's not the oil boiling. But dissolved or entrained gasses in the oil can lower it's vapour pressure. So air in the damper get's mixed into the oil, some disolves some remains as small bubbles, as you cycle the shock one side of the piston experiences very low pressure and the other side high pressure, so the bubbles get big, then collapse. Obviously big bubbles don't damp very well which is why it's bad, but they can also cause damage when they collapse as they move away from the low pressure region, but I've never heard of this happening in a shock, it's more common in poorly specified boat propllers or pumping systems.