Miyata 210 gearing.
So I finally got around to working out the gearing on my Miyata. Turns out the chainrings are 50/44/26. Scratches head, what are the chances it was built that way?
I can't see any gotchas in changing the middle ring to a 38? It would certainly suit my commute better.
50/44/26 ... that'd be half-step plus granny style gearing. the idea was that the step between the 44 and 50 would be half as much as a single step in the rear, so you could get gradual and consistent steps by shifting the front and then the rear + front at once, etc, and still have a nice bailout gear. with 7, 8, and 9 speed wide range cassettes, there are enough intermediate steps, so you don't see this gearing any more.