Originally Posted by old and new

I would it as it is. Many suggestions have arrised,I could find fault with any of them, I'll address a few. First off,
it's a 1981,most likely. If it's an '80,it would be the first '80 610 i've encounterd with SunTour, '79s didn't exist to my knowlege,it could be gray market though,that's a stetch. Then again the frame size is as well. Miyata's big push into the market started in late'79 with the introduction of the'80 models, prior to that, Miyatas were few and far between. If it has a plastic head badge,it's an American market '80s, painted logo,a '78,early '79.The # you give MIGHT be a J, not a T. As far as component changing, problematic : It has 27" wheels, P I T A to find a set of wheels that would make a meeningfull improvement. A set of Suzie hub'd ,Ukai or other such wheels just
MIGHT make a difference,not worth it. Anyone who actually knows/has/had that bike as I do,knows that the OE wheels are plenty strong. B T W, I weigh over 220,NEVER crunched or bent a wheel, then again I don't AIM for rocks and ruts. Spacing, a problem, it shifts well now, it won't after you start rubin'-up the drivetrain. What's the point, a few extra gears? Look at your ring gears, if it's not a triple,it's an SR 36T/50T crank, who says compact gearing is a "new thing". I also strongly disagree on the brake question..too questionable, besides, anybody who's ever had old Diacomps, KNOWS that they just plain STOP. I could go on,I've alread waisted enough of MY time and YOURS. Leave the bike as is. rather than throw 2 to4 hundred at it to render it OK, leave it near perfect, why pretend you ,I or anyone knows how to formulate a better tourer than Miyata. That bike was made in the touring hay-day, the Hight of knowlege as such. save the $$ to find a second bike, OWN 2 !