QuestionHD 1991 Fat Boy, original title in CA, been in Midwest for last 6 years. We put over 2k miles on it last year, with little to no trouble. This year, rear plug keeps fouling out. Took to HD dealer mechanic, they rejetted the carb (Slow Jet 27170-89), changed the plugs (SR 6A), new ignition coil, new wires, new battery. From moment they brought it out of the shop, it was puffing black. On way home (6Mi) it progressively ran worse. Backfiring, missing and simply didn't run right. They picked it up again, claimed I had fouled the plug again. It ran for that day (approx 200 miles) fine. Next morning, using the choke per their recommendation, it still fouled the plug. Cleaned the plugs... Using no choke, doesn't matter, still runs terrible. At a loss here as to what to do now.
Thanks for your time.
AnswerFIND A HARLEY DEALER WHO KNOWS SOMETHING ABOUT HARLEYS.
INSTALL #45 LOW JET MAKE SURE NEEDLE JET IS STOCK AND NO WASHERS UNDER IT, 160 MAIN JET AND TURN AIR/FUEL RATIO SCREW OUT 3 FULL TURNS FROM SLIGHTLY BOTTOMED. INSTALL NEW NGK BPR7ES SPARK PLIGS GAPPED AT .040" AND TORQUED TO 20 FT LBS. JOHNNY 602-705-7474 YOU DID NOT TELL ME WHAT EXHAUST SYSTEM YOU HAD ON THE BIKE??.
