not scientific..... I ride 175 (5" 11" 32 inch inseam)
I really notice it if I am riding 165.....feels like I am spinning like a rabid squirrel. I replaced 165 wit 170 on my around town bike (what I could find in Arabesque....so will have 165 up for sale soon) and it is way better, need to ride this set up some more
my 84 miyata has 177.5 and I don't really notice that compared to 175
this is all of interest as I am considering getting a Rene Herse crank set and options are 171 and 177
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