Bear in mind air will expand with the heat generated as the shock works , possibly to the point that you blow the seals . Also air contains moisture which won't help the internal components , if at all possible , get them nitrogen filled . They will work better and last longer .
Any top tyre centre or suspension specialist will do this for you !
Under normal operating conditions - I would not expect excessive gas expansion due to heat (unless the lubrication fails which would burn the seals out before they blow). It's only a ruddy shock absorber.

The pressure being above atmospheric should eliminate the chemical reduction of water enough such that it would generate corrosion. If you really want to get picky in a damp climate - talk to Hill Pumps ( Ernest H Hill Ltd In Sheffield) and get them to knock you up a stirrup pump with a low pressure humidity filter. I have one of their 200bar pumps. This gives 90% dry air.

Fournales supply low volume/high pressure stirrup pumps for their shocks - I think we can assume therefore that Fournales should use air and NOT Nitrogen.
 
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Under normal operating conditions - I would not expect excessive gas expansion due to heat (unless the lubrication fails which would burn the seals out before they blow). It's only a ruddy shock absorber.

The pressure being above atmospheric should eliminate the chemical reduction of water enough such that it would generate corrosion. If you really want to get picky in a damp climate - talk to Hill Pumps ( Ernest H Hill Ltd In Sheffield) and get them to knock you up a stirrup pump with a low pressure humidity filter. I have one of their 200bar pumps. This gives 90% dry air.

Fournales supply low volume/high pressure stirrup pumps for their shocks - I think we can assume therefore that Fournales should use air and NOT Nitrogen.
Ah ha , assumption , the mother of all **** ups . Not being an expert , i cannot offer a valid argument . Other than to say , many bikes I have owned have been equipped with air / gas assisted suspension , some running at very high pressures. Whilst a few have stated only use nitrogen , all have recommended nitrogen to maintain stable pressure ! Sure one can buy a filtered pump or such like , but at what cost compared to penny's for a squirt of nitrogen . As for temperature ranges during normal use , touch any suspension reservoir after a spirited ride and it will be on the hot side of warm !
 
JEEZ Patrick - Just because Fournales run at 18bar - does NOT mean those do.
The external air adjustment on remote reservoir shocks ARE NOT for Springing.

ime of remote damping reservoirs anything over a couple of bar is enough. Adding more pressure affects the overall damping rate - And ime of Heavy unsprung rears: resisting immediate damping response is NOT a good thing. I'd drop them to 3bar straight off.

Using air SHOULD not be an issue IF the reservoirs have an isolating diaphragm - Which they should do if designed for inverted mounting. The air adjusters pressurise the diaphragm which applies pressure to the chamber on the other side.

fear not I have reajusted the pressure down and playing with the reactive spring also
 
Ah ha , assumption , the mother of all **** ups . Not being an expert , i cannot offer a valid argument . Other than to say , many bikes I have owned have been equipped with air / gas assisted suspension , some running at very high pressures. Whilst a few have stated only use nitrogen , all have recommended nitrogen to maintain stable pressure ! Sure one can buy a filtered pump or such like , but at what cost compared to penny's for a squirt of nitrogen . As for temperature ranges during normal use , touch any suspension reservoir after a spirited ride and it will be on the hot side of warm !
Rather than pure nitrogen, I used nitrous oxide, and just laugh at the bumps. :p
 
As for temperature ranges during normal use , touch any suspension reservoir after a spirited ride and it will be on the hot side of warm !
Guess - 50C 75C 100C?
Rather than pure nitrogen, I used nitrous oxide, and just laugh at the bumps. :p
Would those be SPEED bumps?
 
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