I just swapped engines on my Fatboy. It runs great but after about 10 or 15 minutes the oil light will start coming on. I can rev the engine a bit then it goes off. But eventually it stays on. I then turn off the bike for about 30 seconds and start it back up and the oil light is off again for another 10 minutes. Any ideas???

Thanks in advance!!

 

First step would be to check the oil, do you have enough?

Then, I'd put a pressure gauge on it and see what kind of pressure it's running. Evo's don't run much oil pressure, particularly at idle. You can get them cheap on eBay, you can replace your lifter screen screw with an adaptor and a gauge.

Tell us more about your new engine, was it rebuilt, new to you but from a junkyard, or what?