Have you cleaned your pick up screen? It could be blocked and the passage from the screen body is narrow. There is a mod from a member on the cb1100f.net site that sells modified screens to allow more oil to flow through. Your oil pipe could be blocked as well. It delivers the oil from the case to the head. It’s the s shape pipe on the outside of the case. I’d try these first. You’ll have to drop your pan to inspect the pickup screen but it may be worth it.
What is stock tickover pressure specification? That sounds really low.If it's as low as it sounds, teh reasons could be blocked inlet or a spun bearing that's allowing oil to just piss out back into the sump.
like i said you had the wrong shop 60 psi is about the relief pressure i would expect around 20 psi hot idle 30-40 cold idle
From what I read on the cb1100f.net forum you want about 10psi at idle and 80 when riding. Check your oil pressure relief valve as well.