I hesitated after rereading my post about whether or not to hit "Post Reply". I am a noob bike craftsman, I have not even finished my first trike build, but I think I might have an idea for you to think about.
I spent 17 of my 20 years of my USAF career working on/around the KC-135 aircraft as a Hydraulic Specialist (started off being called a Pneudraulic Specialist) and as I got to the end of this thread I kept screaming in my head, use some compression type fittings (Military Standard or MS), or better yet, some flared tubing and B-Nuts (Army/Navy or AN). Here is some information about these fittings.
http://avstop.com/ac/apgeneral/plumbingconnectors.html
http://pipeandhose.com/node/16
Then again, maybe I'm just missing something about your build.
The MS fittings would be easier to use and operate, but you could still have a ball type valve and a fitting to disconnect the tank from the system and the bike would remain pressurized.
I guess I'm just trying to relate it back to the old aircraft that I worked on and kept in the air. Between the high pressure air for the accumulators (roughly about 1,000 psi) and the pressurized fluid of my hydro systems (3,000 psi) we could tell when there was a leak.
The Electrical/Environmental Specialists dealt with the low pressure oxygen systems on the jet and used the same stuff I did. On a side note, as a Production Superintendent, part of my job was reviewing aircraft forms when a plane came back from a trip off station. I could tell if there was a chronic leak of the oxygen system, or if the Crew Chiefs that took the jet out were hung over most mornings and using the oxygen to help get them over the hump.
The bottom line is that there is some normal types of servicing, mainly due to the ambient temperature fluctuation, and then there is the chronic leaks with write ups or the abnormal servicing of the oxygen system.
Oh, yes it does work! A good cure for a hangover is a couple of deep breaths from 100% pure oxygen, and yes unlike Clinton, you have to inhale and hold it it. I'll just plead the 5th on whether or not I actually had to do this in my younger days....
To help find the leak, here is how to build up a leak detector. You have to find a small squeeze bottle of some type. If you use an ear wax removal kit, fill up the wash out bottle or one of those red/yellow ketchup/mustard bottles (mechanical spray bottles won't work) with a mixture of liquid dish soap (one good shot of soap) and water. Gently squeeze it out over all of your fittings and where the rod's exit the actuator, of it bubbles a lot, you have found your leak!
Cheers,
