It might be the oil pump itself.Mine lever was staying open when I came off the throttle and it took forever to come back to the idle position.I tried spraying the arm and cable with no luck.I found a bag of springs at an auto parts store. One of the springs was like a ballpoint pen spring about 2 inches long.I threaded the spring over my oil pump cable at the pump end and the problem is gone.
Sledding and biking since 1968.
04 King Cat Titanium 162.
2010 Harley XR 1200.