Crank Size Help

175, maybe longer, harris cyclery has 175mm shimano 105+BB on special this month. 😎

uphillbothways said:

Could someone give me a quick intro to crank length. I need to replace my current crankset and I am not sure what size I should replace it with.
I am 6'1, 34" inseam. Most of the riding I do is flat. Some hills, but no big deal. Should I be looking at something like 170mm or 175mm? Thanks. Also, My current crankset is a Shimano 600, fairly beat up. Would I be wrong to save a few bucks and get a nice 105 set instead of Ultegra?

In one of Chris Carmichael's books (it's either The Ultimate Ride or the one he co wrote with Lance Armstrong circa 2001) he says that someone of your height should use 172.5 mm cranks. Though with that said, Lance Armstrong is 5' 10" (same as me) and he uses 172.5s (I think). So LA doesn't use Carmichael's formula. I use 170s and they work pretty well for me. I'm more interested in higher rpms than pushing a higher gear though. Someone on this forum said that you probably wouldn't notice a difference between the 2.5 cm increments. An no, I doubt you'd notice a difference between shimano 105 and ultegra. Ultegra is way cool though. 🙂