Originally Posted by
Gharp23
I am curious as well. I am 5'9 and ride a 20' frame with 175 cranks. Would it benefit me to downsize?
20' frame?!
But seriously, if you're comfortable with the 175mm arms, there's no compelling need to change. Longer arms give (slightly) better leverage; shorter arms make it (slightly) easier to spin. For me, the only compelling reason to seek a specific arm length (165mm) was to improve cornering clearance on my fixed gear bikes.