Mark, If your old knees need a lower small ring in a 70's vintage crankset, another one to consider is the 1st generation Shimano Dura-Ace crank. With the Shimano 130mm bolt circle diameter, it handles down to a 38 tooth chainring (usually comes with a 39t), with the added advantage that chainrings in this bcd are available from current production and all the way back to 1973 or so, from Shimano and dozens of other manufacturers. I recently bought two used sets, the second of which comes with a pants guard ring mounted on the 52 tooth ring, nice for cruising the town in street clothes! The 70's 1st generation version is classic looking in a Japanese technical kind of way, but not quite as beautiful as Nuovo/Super Record cranks of the same era, IMHO. You can't have it all, but you can try!
Tony (Eating my Cake) Winters in Center Moriches, NY USA
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