I'm not sure on a road king or a 1999 but I had a 2000 FLTRSEI which started life as a Magnetti Marrelli Fuel injected bike. As I changed out cams, pistons, etc the MM EFI became problematic so I did as Scott suggested above and converted to carb and things were fine for many years.
Fast forward to a few years ago and my bikes lower end needed work after 100,000+ miles so I opted for a 117. It ran good but below 50 degrees and sometimes when hot it would be a bear to start?
I converted that bike to Delphi and it wasn't too hard. My bike had the two screw in quick release fuel lines. (some bikes maybe yours had hard lines in the tank). Being originally Carbed you would need a fuel injected tank or someone to weld the fuel line bung in your tank. I blocked off one of the lines with the pingle block off fitting. I used Harley's coil, ECM (flashed to a 2002 VIN), and the factory fuel pump for Delphi in the fuel tank. I went with an HPI throttle body, yellow band injectors and all Harley Davidson sensors. You need to make an adapter to mount the coil in the factory location. If you want to go with the factory ECM you will need to marry a TSM/TSSM to the ECM. I had Dan Thayer make a harness for the conversion and marrying the TSM/TSSM.
Before the conversion I had occasional kick backs, went through a few starters and ring and pinions. After the conversion all those issues disappeared. I believe I had about $3000 in the conversion.
Last edited by thealien; 06-03-2016 at 06:29 AM.