Lots of technical information from the main original equipment chain supplier to Triumph. The Italian Regina product has also been used for fitment to new bikes, but for us DID (from Daido Kogyo) is the preferred option. This link is to the US website.
After linking to their website, click on ''engine controls'', then ''inductive ignition'' and finally ''ignition technology explained''. There is then a choice of excellent working illustrations of different aspects of ignition systems from one of the suppliers to Triumph of the ignition components. Triumph on early models used both PVL and Gill for ignition components.