I have a 2014 Road King, it's my plan to keep it completely stock except for a muffler change. It has the 103 High Output engine, new for 2014. It has more than enough power as is, runs beautifully, I can be on the freeway in 6th gear, and at 60 MPH, without downshifting can pass other vehicles effortlessly.
I hope to get 100k plus out the engine.
Previously I had a 1990 Springer Softail, never used oil, the only weak link was the battery, had to change it out yearly, of course that was 1990 technology.