Low oil pressure, check the pump and relief?

From what I understand, the pressure relief valve (if seated correctly, with a good spring, and no surface wear) should only limit the high pressure. I believe I read somewhere that 75psi is when the valve on the KZ650 should open. I believe the bike is behaving properly when cold,

For the 650 only the hot, 4k oil pressure is spec'd. The spec is 28-36 and I'm reading 22. I don't consider that to be "significant" according to the FSM, especially since the oil light isn't coming on anymore at idle. Oil pump, bearings, and chain,checks will be on my short list for winter projects.

I've always been very easy on my cars , bikes and trucks for this reason ...... let that oil and motor warm up a little before any kind of load.