Motorcycle Repair: Evo low oil pressure, low oil pressure, strength spring

Question
Yes, flow is good thru feed line.  I removed oil tank and flushed it in case foreign material was blocking the line. I also replaced the feed line from tank to pump. Oil lines are right, I went out and checked again with the manual. Thanks
Ed
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The text above is a follow-up to ...

-----Question-----
Mike, I have a 1989 Softail that has suddenly lost oil pressure when it is hot.  I don't trust the light so I installed a gauge. It reads 15-20 lbs. until the bike is fully hot (20 miles of riding, then the pressure quickly fades to nothing and the light comes on. I have removed and inspected the pump- no grooving on the body, no sheared keys, everything looks good.  I replaced the oil pressure check valve spring with a higher strength spring.  This keeps the pressure at idle at about 5 lbs. and the pressure at road speeds at about 8-10 lbs.  Any ideas?
-----Answer-----
Do you have good oil flow out of the oil line going to the oil pump? Also, you didnt get the lines back on wrong did you?
Mike

Answer
Your pump is not creating enough pressure to feed the motor so you will probably have to go with a stronger spring. Even though there doenst look like any damage to the pump body there should be a certain clearence between the gears and body and you might be loosing pressure that way
Good luck and happy riding
Mike
Good luck and happy riding
Mike