Hey Dg, the only other thing that I can think of based on the shut off and restart and all is good for a moment, is it possible that you have a lifter bleeding down? It's the only thing that I can think that would cause that. How many miles on your lifters. Everything in the motor is roller bearings that don't help to build the oil pressure, It's possible that there is too much wear at the plunger of the lifters when hot. Too much clearance will cause lower oil pressure at idle. The only other thing would be lifter to lifter block clearance too high when hot allowing the oil to go back to the cam chest and not through the lifter which again will cause lower pressure at idle. There should be specs on the lifter block clearance. I believe it .003" I don't have my manual handy. Maybe someone will chime in and get you that spec....a good pair of vernier calipers should work.

 

The engine is all new with probably less than 500 miles on it. I used all new parts. Other than the cam, the breather gear and oil pump, everything else came from HD. Should I swap out the lifters or is there a way to test? Fortunately, I do have an extra set of new ones in the garage.

 

Um, why put an old oil pump in a new engine? Just asking.

 

The oil pump is new, but it is not HD, its an Ultima, Andrews EV13 cam, and S&S steel breather gear. All other parts came from HD.

 

Sorry, I remember reading that now!

 

I don't trust the Ultima oil pump. See waynemags post above. Your motor. Do what you want.

 

If I had a bad lifter, wouldn't I get a knocking sound and a miss in the engine? The bike sounds and runs great. After all of the negative reviews of the Ultima oil pump, I am going to order a new one tonight. I bought this bike in a thousand pieces and got boxes of new parts along with the oil pump. Also, what about the oil pressure sending unit/switch? Could this be the culprit? Is there a way to test it? Thanks again

 

It could certainly be the sender, as was suggested in the first reply. Pegging at start then dropping to zero makes it very supect. I'd replace it first before the more expensive things. I'm not aware of a way to test it, but maybe someone will have an idea on that.

 

The sender is a mechanical device. Pressure pushes against a spring loaded arm which rides on a variable resistor, like a gas tank gauge. I'm going with the sender isn't the problem. You could always put a mechanical gauge in its place and see what is really going on.

 

Are both the preasure sender and oil light sender in the same location?
Maybe some crud in the line below the t?
Only a problem of some sort in the line would make both read low pressure at the same time.
It would not hurt to check it out.