I've been reading a lot of comments about oil pressure on HD's. No, this is not a, "Idle vs. Riding PSI" question. Some folks have been saying that high oil pressure is not such a good thing. A few years back I did a cam chest upgrade. Fueling. It included a new HV oil pump. (I get 60PSI, warm, at speed.)

Some advocate HD engines are not intended to be "oil cooled". So, an oil pump that produces 60 PSI is a complete waste of money. Others say the additional pressure (OEM mid-30"s PSI) is going to cause problems. They dis the idea about the benefits of an oil cooler, too.

I'd very much appreciate hearing what others believe to be true ...and why. TIA.

 

 

Excessive oil pressure can create problems, one being excessive flow to the top end, picking up too much heat from the heads and cylinders, forcing the need for an oil cooler as well. Excess oil pressure forces the oil relief valve to run wide open when it's not intended to be, either recirculating the oil through the pump or dumping it off to the oil chest. All this extra oil can burden the flywheels and pistons robbing horsepower, overtax the oil return pumps, overwhelm the oil separators making for more breather misting and carryover.

 

At idle (hot) 15, at cruise 50 on my bile for the past 7.5 years.
Lifters certainly want pressure even if bearings do not. Low pressure and you get the knock. The piston is sprayed with oil, These are oil and air cooled engines.
Not sure why some say high pressure is not needed, or hurts the engine.

 

 

From the factory service manual

Engine oil should be at normal operating temperature, 230° F
(110° C), for an accurate reading.
5. Oil pressure should be 30-38 PSI (207-262 kPa) at 2000
RPM and normal operating temperature.

 

Thank you for your reply. I do not expect everyone to do it my way which is also proven by pros. You are free to ignore that the relief springs are not all the same, do collapse with heat lowering pressure. You are all free to continue to follow my sig line. I will offer this link for the replacement spring I installed.
Baisley

 

Producing 60 psi actually creates heat...something you really don't want on an air cooled motor.

Oil coolers only work when you don't need them...sitting in a traffic jam with no airflow, an oil cooler does nothing.

 

Pretty happy so far with my fueling pump and baisley spring. I will agree on one thing it seams to bring on my ultra cooler fans more now, but still not very often here in Michigan. So to me it's not really a bad thing that the oil is taking the heat away from the motor. 121,000 miles on my bottom end. Oil and cooling has been my priority from 69,000 miles when I bought the bike and had to rebuild cam chest that summer.

 

It will if it has a fan.