I have a 2005 FLSTCI and have just upgraded to a Screamin eagle hydraulic cam chain tensioner and oil pump and fitted an oil pressure gauge, when I started the bike the oil pressure was up around 40psi, as the engine warmed up the pressure started to drop to a point where at idle the gauge reads 0psi, if i open the throttle a little the pressure goes up to 10psi, is 0psi at idle with a warm engine something to be worried about?

 

What is your idle speed? Seems like I heard something about newer bikes being 900 to 1000 RPMs for just that reason. Just a thought.

 

Are you using the gauge in the dash or an external gauge?

If dash gauge (sometimes not very accurate), try hooking up an external gauge and read again. If it's still reading 0 psi then a little concern is noteworthy.

 

HD says 6 lbs at hot idle is good. My gauge is bolted to the lifter screen port and cold its 30-40 lbs, hot normal it drops to 8 or 10 lbs at idle. Normal running dn the road its at 25 lbs which is a good press all the way round.
Hot summer temps 90*+ your oil will thin and you get lower pressures so you need to go to 60wt oil to get proper pressure.

Also trust what your gauge is telling you, that's what it is for...... They are fairly accurate. Also keep your idle close to 950-1000 rpm for best oil pressure and least wear on engine parts.

 

Idiot light is more accurate than a gauge. Is your idiot light on? If it isn't than your probably have at least 6lbs of oil pressure. I would check the gauge with a better gauge if the idiot light isn't on.

 

The idiot light will go on if the pressure drops below 5 psi. Your gauge is probably off a little. As long as your oil light isn't on, your good to go.

 

The idiot light is your friend but it is an idiot light. Some mechanics will tell you 0 pressure at idle is ok but not on my bike. that idiot light will stay off if you have 5 lb of pressure if its working. True that if the idiot light is off you are probably ok but I had rather have at least 6 lbs or more as HD states.

 

Most oil pressure gauges have a scale whose increments become closer together as it approaches zero. Accuracy in the last little bit of travel is highly unreliable. If you truly want to know the oil pressure, at idle, you'll need a gauge with an expanded lower scale.

 

Isn't there something about when you do the oil pump you can screw up the pressure relief system and this causes low oil pressure? I am pretty sure I read it somewhere.

 

Okay bone pickers. Three of my repair manuals say between 4 to 8 lbs the idiot light will come on. The point is that if his light isn't on and the gauge is zero. It is most likely the gauge. Put on a new gauge before getting too worked up. A good gauge and get a true pressure reading before proceeding on. Any mechanic that tells you zero lbs. of oil pressure at idle is okay is an idiot whether he has a light or not.