G'Day. Can anyone help with some advice on a possible cause of a misfire with my 1980 XS1100. The old girl idles fine ( most the time ), accelerates fine ( except from low rpm ), cruises fine ( most the time ), BUT it has a misfire, where it looses spark to both 1/4-2/3. Only momentarily but annoyingly , I've replaced TDI ,checked coils, checked negatives checked pick ups , checked timing - carbies are good and working fine, I'm sure it's in the ignition but can't find the problem - if I weren't already bald, I would be now. Any help would be great thanks