I had a problem with the ignition switch on my 750 on the way to the Dutch TT back in 1984...I remember it so well.
My brother's silencer/collector from His Harris 4-1 had fallen off on the A2 on the way to Dover so we had all pulled over to watch him try & retrieve said exhaust part from the fast lane of the fast bit of the road. Once he'd got the flattened part back, I went to switch my bike back on so's to continue on...except it was dead...as a door nail. Once I had ascertained that it was the switch that was faulty, I bypassed this & got on the way again.
When I got home I took the ignition switch off & took it apart. With a mass of springs & copper links inside, that were quite badly corroded & burnt, I knew that it could be rebuilt. I used a points file to clean up the surfaces of the contact links & then tinned them with solder. Once back together again it worked perfectly.