Sphere specs

[white exec]

Can someone help me with this one...

Traditional (pre-C5) spheres carried a spec something like
450/50/0.7
where the last figure is the diameter of the damping orifice in mm.

C5 spheres are spec'd differently, eg
385/57/1.9-1.3
- two figures for the damping

What do the two figures relate to? Could it be fluid in and fluid out - i.e. bump and rebound?

[GiveMeABreak]

I think it still refers to the diameter - the older systems (pre C5) operated on a high pressure system, but IIRC the newer Hydractive C5 systems user a low (or lower pressure) system with the slim line spheres - so I'm guessing they would need to be wider. Some of the Sphere sites actually show the last figure as 1.5 - so somewhere in the middle of what you have quoted at 1.3-1.9.

[white exec]

Not convinced, Marc.
Other C5 mushroom spheres' damping figures are 1.75/1.3, 0.7/0.48, 0.9/0.48 1.4/0.94 . . .
Don't see why Citroen would suddenly have gone all approximate with respect to these apertures.
As tolerances, the variance is huge - eg 0.9/0.48 - that's getting on for twice the diameter, ie four times the damping area.

C.

[myglaren]

Is it possible that the inlet and outlet damping is different?

[GiveMeABreak]

Well, one way to find out for sure - email the sphere shop...
http://www.sphere-shop.co.uk/
On the XM with Hydractive II, front and rear regulator sphere damping holes were 1.1mm - double the the diameter of the suspension spheres (0.6 Front 0.5 Rear).

[GiveMeABreak]

Not convinced, Marc.
Other C5 mushroom spheres' damping figures are 1.75/1.3, 0.7/0.48, 0.9/0.48 1.4/0.94 . . .
Don't see why Citroen would suddenly have gone all approximate with respect to these apertures.
As tolerances, the variance is huge - eg 0.9/0.48 - that's getting on for twice the diameter, ie four times the damping area.C.

Well, I dug this up from my archives and as you can see for the front C5 (2002) Slimline spheres, the diameter is very near to the figures you've shown and these are listed under the Diameter of Damper Hole column: So they do seem to vary significantly based on the Engine type.

[white exec]

Yes, that's exactly where I got my figures from - the 2002 Private Cars C5-Synergie booklet.

All I'm trying to establish is what the two damping figures for each sphere actually mean.
On older spheres (eg XM) only one figure appears.

[electronmirror]

Could the different damper hole sizes be anything to do with differences between Hydractive 3 and Hydractive 3+ ?

Just wild speculation really 'cos I don't fully understand the difference between the 2 systems but when you look at sphere specs for the Xantia there is a marked diffference between Hydractive and non Hydractive damper hole diameters.

Doh. just re-read the table and it identifies Hyd 3 and Hyd 3+

[GiveMeABreak]

Don't want to go too off topic here, but looking into this Sphere issue - I was interested to find a couple of links to pictures of inside the Saucer spheres - in this case comparing an IFHS Sphere with a Citroen Original Sphere.
Inside an IFHS Sphere

Inside a Citroen Original


The point being that according to the C6 guys the IFHS, MONROE and SUPPLEX saucer spheres are the same inside as the old green LHM spheres in terms of membranes and don't last as long as they still suffer with the nitrogen slowly escaping.

The Citroen genuine spheres have the newer membranes which seal better, reducing nitrogen seepage and allows Citroen to guarantee them for 5 years / 200k Km.

Guess I know which ones I'll be replacing mine with!
And back to the topic - no extra damping holes inside the sphere as far as I can see.

[Stickyfinger]

So ?.....no "Spike" then

[GiveMeABreak]

So ?.....no "Spike" then

The spikes component may have been removed to show the membrane better - here's another pic showing the dreaded spikes!

[Stickyfinger]

ahhh-ha.....little tinkers

[elma]

Is it possible the dampers are tapered holes?

[white exec]

3 and 3+ ? Think not; the table above relates only to Hydractive 3. In addition, a single sphere with a single part number carries the two diameter figures.

Is it possible the dampers are tapered holes?

Maybe, but I can't see that affecting fluid flow in each direction by much - limiting factor is the smallest diameter.

Bearing in mind that these mushroom spheres have been around for years now, I'm amazed their workings and specs are not better understood.

The detail about genuine Citroen and pattern membranes above is very interesting, and certainly points towards which spheres ought to be used, if sphere life is a deciding factor.

One irksome thing about the new mushrooms is the lack of a readily removable threaded plug, which enables a Tecnosir valve to be easily installed. Tecnosir do offer a 'C5' valve, but fitting it involves drilling and threading the sphere crown, something which Citroen prohibit, and many folk would baulk at. Maybe the trade-off is the proffered long life of the new spheres.

The mystery of the damping diameters remains...

[GiveMeABreak]

Not that it's relevant now, but H3+ is in the table about half way down.
Although I've seen comfort spheres for the C5 Mk 1 & 2, I haven't seen any for the X7, and I suspect it could have a negative impact on the vehicle with a 7 sphere setup on the latest system.

I saw the saucer sphere thread replacement too but don't fancy that!