sachs rear monoshock question?

[scre103]

At one end of the reservoir is the click adjustment at the other is a screw off cap. Is this port used for adding air to the res or oil? If it is air and the res is empty what effect will that have on the shock? thnx

[GuzziMoto]

At one end of the reservoir is the click adjustment at the other is a screw off cap. Is this port used for adding air to the res or oil? If it is air and the res is empty what effect will that have on the shock? thnx

The air valve looking thing on the bottom of the reservoir is where you pressurize the shock with nitrogen. On remote reservoir shocks that nitrogen usually fills a bladder in the reservoir that applies pressure to the oil. The pressure on the oil helps keep the oil from foaming. If the oil foams, the dampening fades. Do not release the nitrogen from the valve. Do not even try to check the pressure with a gauge. It is under very high pressure (over 125 psi usually) and it is a very small amount volume wise so that any loss has a large impact on the pressure in the shock. If you have let the air out, I would take it to a shop that services shocks and have them recharge it. Some people have recharged theirs themselves, but it takes a special rig to do it properly. For the little bit of money it costs to pay someone else it is not worth the time and expense to do it yourself in my opinion.