Thumbing through my archives I found this Triumph Service Bulletin from February of 1973. Keep in mind, I’m publishing this purely for entertainment value, not for reference or operational use. It describes upgrades they made to their 5-speed gear set and changes in parts availability. One of the biggest challenges for any manufacture is keeping their dealer network aware of real time changes and upgrades. Service Bulletins are just of one of the many ways they all still communicate with dealers today.
I have always been a fan of these retro-styled bikes and vintage or historical advertising or service literature. I think this qualifies as both. Enjoy!