May 19, 2011 11:44 PM PDT
here is my 3cents, when I had my 86 883 I use mobil 93 all the time ran great. then bought a 87 fxlr custom lowrider and ran the same mobil 93 to this day I still have both bikes, one with 69k on sporty, 42k on fxlr.
Just a year ago I bought the fatboy lo and from day one sunoco 92, along with amsoil 20-50. so running 91-93 grade of gas will not hurt your bike harley's, other bikes not sure some of them call for lower octane.