Originally Posted by itsatdm
A related "what if question" I have Kayaba USD forks with a threaded air bleedoff screw. What affect would there be if the screw was retightened while the fork was compressed?
"What if" questions are the best kind of question... and frequently how people come up with spiffy new ideas and ways to do things.
Much like a fork builds positive
pressure from use, a temporary negative
pressure (vacuum) would be created.
Either would need to be "released" to reestablish atmospheric pressure... which is the pressure value manufacturers consider when establishing air chamber volume baselines and range of adjustment.
Air volume/pressure has a substantial effect on fork function... the reason why fine tuning the stock chamber volume is a worthwhile endeavor, and why add-ons like fork subtanks are becoming increasingly popular with multi-purpose bike riders.