Hello Richmond,
Firstly, may I question whether you really have a 1954 Dragonfly? Whilst this model did appear in 1954 for the Motorcycle Show, they were not made available to the public until about half way through 1955. Also,'Douglas Dragonfly' trips off the tongue and a lot of people think any Douglas is a 'Dragonfly'. The earlier model - the Mark 5, and the early Dragonfly had Douglas brakes - later Dragonflies had British hub brakes. The easiest way to differentiate is to check out the back plate - the Douglas brakes had a cast alloy back plate, where as the British Hub had a steel backplate with a pressed alloy cover. The cast alloy backplate of the earlier model has a reputation for premature wear if it is not kept adequately greased. The only way of restoring the original fit is to have the 'top hat' shell bearing ground to a good finish, then bore out the backplate and clean up the faces, then sleeve and shim up the bearing to suit.
If you provide a frame number, we can identify your machine more exactly, and may even be able to give the date it was dispatched from the factory.
Regarding your conversion to 12 volt and the fitting of a Maplin ignition kit - this will overcome some of the problems with the Miller ignition system, but the main problem centres on the wear in the distributor bearings, and also the fact that Miller points are now hard to obtain.
Regards,
Eddie.
