UPDATE…..Following a Google link for Lucas Magdyno MDB 1, I was taken to a Brough Superior site with comprehensive diagrams and service instructions relating to a Lucas Magdyno MDB,MDBR 1929,clearly showing the “F” and “D” terminals. Whether a previous owner fitted this item to my 1936 FS or whether it was original,I don’t know,but at least I can find the details I was looking for. If it was good enough for Scott then it should be good enough for a lesser bike !!!!
