I noticed something a couple of days ago that has me questioning what might have been done to my bike by the previous owner. When riding home the other day, I noticed the oil pressure fluctuating and the pressure showing higher than it should be at idle. After it had cooled off I removed the sending unit and and installed a mechanical gauge. When started again, the pressure was showing 44-45 lbs. at idle. When revved to 2000 rpm the pressure was 60-62 lbs. Way too high according to the service manual and everything I have read on here. The previous owner changed out the gauges to Dakota Digital units. I did verify that the oil pressure gauge was set to work with the OEM sensor.
Upon re-installing the sending unit, the gauge fluctuated from 38-44 at idle, but dropped to 8-10 lbs at 2000 rpm. I figure the sending unit is bad. It is an OEM Harley unit. Still the high pressure that was showing on the mechanical gauge has me concerned. The oil temp when I ran the tests was 180-190 deg. There are no strange noises and no oil in the air cleaner. I'm thinking it may be time to crack into the engine and see what I find.
Some details about the bike.
2008 Ultra Classic 62K miles, Vance and Hines Hi Flow air cleaner, full Vance and Hines Exhaust & HP3 tuner. Not that it matters, but the previous owner added Screaming Eagle plugs and wires as well.That's it for modifications as far as I know. Thoughts, opinions, advice welcome. Thanks all.

 

Sounds to me like something got caught in the pressure relief valve. One thing to realize is that the pressure relief valve is before the oil filter.