just looked again...and I understand what confused me on the only right hand shifter boss on the koga miyata..I am pretty sure .it is a boss for the lever that engages the generator.

just for fun I looked at a US spec Miyata catalog I had a link to (1989) the top end steel race bike the Team was listed as 21.4 pounds, the 1000LT touring was listed at 25.2 or so

go for the miyata (and visit your parents )