If your oil level is correct, the light should only illuminate while starting, or when the ignition switch is on and m/c is not running. Changing to S/E syn 3 should have no bearing on anything. There may be an underlying problem. Does this engine have high miles? What is this engines history? Has there ever been any work/upgrades done to this engine? Make sure it is not just something silly. Check, or change your oil pressure switch. Be sure that the wire/wires for the switch and indicator are ok, and not pinched anywhere.
It never happened until I changed oil and went full synthetic. I was just talking to a friend he said it might be because it has just under 78,000 miles no work ever done. Do you think it might be the change from H – D 360 20w50 to the screaming eagle syn3 full synthetic?
You should not have this problem using 20w-50 weight oil. Doesn’t matter if it is synthetic, non synthetic, made by: HD, Spectro, AMS oil, or Mobil. There is something else causing the oil light to illuminate. May be as simple as a dead short in the oil pressure switch, or indicator light wiring. Or an engine problem. If you switch back to the originally used oil and the light stays off, the found problem is not fixed. Look for any Harley error codes.
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