These all go back to the alternator and marked on it is model no RM14
Dark green / black tracer.
Light green / black tracer.
Dark green / purple tracer
Dad is suspecting that at some point an aftermarket alternator was fitted to this bike hence the issue with the 3 strange wires with tracers in them.
The stator output wire insulation usually hardens, becomes brittle and eventually disintegrates from engine heat and primary case oil contamination over time, the copper strands then break (as well as sometimes being sawn into by a loose primary chain) so it isn't unusual to find the original stator wiring has been replaced, usually with whatever colour wires the owner happens to have lying around.
According to the Lucas technical manual of the period, the early alternator wire colours were Dark Green, Mid Green and Light Green, unfortunately Dark Green/Black, Light Green/Black and Dark Green/Purple means nothing to me.
As the RM14 is an early unencapsulated stator it may be possible to identify the wires by looking at the stator.
The information in the link describes how to identify the wires of an RM18/19 stator, but I'm guessing the RM14 could be the same.
http://www.bsa-c15.org.uk/c15_alternator_wiring.htm Some have suggested that it does not matter what wire goes to what but surely it must......
If it happened to be a 3-phase alternator then it wouldn't matter, however the RM14 is a single-phase three-wire alternator, so connecting the wires incorrectly may cause either under or over charging as there is no voltage regulator in the original system.
Lucas tech. sheets:
http://www.britishonly.com/tech/manuals/sb519.asp
