Thanks. That was kinda the answer I was hoping for. I also have the case protector on this 71 which I understand has limited value now with today's chains however I was one of the unlucky ones back in 71 that threw a (new) chain through the case flying 95+ across Texas so I'm a little squeamish about the topic.
Yikes! You were one of the few and the proud.
The chain protector was always put on AFTER someone threw a chain which was timely (not).
While not conclusive, the rumors I heard, and for which there is a Honda service bulleitn, was that the vent hose from the battery was improper length and routing, was allowed to rest above the chain when on the sidestand. The minuscule drop of condensed vapor may have been enough to put a weak spot in the chain, thus causing the often unexpected breakage. Seldom did the break occur when someone was doing drag race starts, etc. Part of the (later) warranty work was to correct this vent tube, thus rendering the guard superfluous.
I was working as a flunkie in Honda shops when this was going on. Too young to be real technical about it, and i still may not have the full story, I did see the damage and hear the stories of many breaks. It was a true mystery at the time and Honda was really struggling to fix it. The vent tube story came out later.
It doesn't hurt to keep it if so inclined. Back to your original post, i can't offer any help.
