3 Vintage Triumph Motorcycle Prints

I found these folded up in a box of old ties and belts at an auction in West Virginia. They are approx. 19 1/2" x 29 1/2". They are in really good condition and i think they were parts diagrams that were put in the box as an assembly diagram for the shop guy at the Triumph factory. I really don't know, just guessing. I took them to a Harley dealership, just to see what they thought. They had never seen anything like it before. At the bottom, there is writting which reads REF .414/58, Triumph Engineering Co. LTD, Meriden Works, Allesley, Coventry, England. Each Drawing is signed "HW Perkins Coventry". They are in very, very nice condition and i have them framed behind glass now, so i don't have to keep opening and closing them. All i know, is i like the parts breakdown of each system and knowing it may be from a vintage bike, is really cool. If you can tell me what i have and any idea of what they are worth, it would be very helpful to me. Thank you very much.