I was thinking more along the lines of the 600 mile service and the ubiqitous "disconnect the battery" that every repair in the Triumph manual begins with. I suspect the battery ground to the frame more than the battery terminal itself, but the starter terminals are another good palce to look. It just can't be a coincidence that the 600 mile service and this happened back-to-back.

A positive attitude may not solve all your problems, but it will annoy enough people to make it worth the effort. Herm Albright (1876 - 1944)