crank length

[VeloVT]

It's amazing how you can really feel a few mm difference. I'm 5'6", 31.5" inseam. I have a bike with 170s and a bike with 172.5s, and I can tell the difference. I prefer the 172.5's because I get better leverage -- it's noticeable all of the time but particularly on hills. I suppose it's a tad easier to spin faster on the shorter cranks, but the 172.5's allow me to spin as fast as I need to (normal cadence on 172.5's is around 90-100; when I get really tired at the end of a windy ride, I might ride in lower gears and spin between 100-110).

When bike shopping I often feel lucky (perhaps even grateful) that I'm very average sized (that is, I'm not petite). I am on the small end of the range where it's reasonably easy to find components to fit (and it drives me nuts how few models of bars come in 38cm, and that my size XS, WSD bike came stock with 40s), but I think it's still much easier for me than for many smaller women.

[HillSlugger]

I don't feel any real difference between 170's and 172.5's on my two road bikes but I had to switch out the 175's from my commuter bike as I was getting knee pain.

[madscot13]

sometimes I'm just surprised at the difference 2.5 mm will make

[KatyLady]

At 5'4", I have a 30" inseam and wear petite slacks. But because I have long femurs (not uncommon for women) I ride a 170 crank very comfortably.

[sgtiger]

5' 1 3/4" w/26" standover, the builders for my custom Rodriguez reccomended 170m cranks for me. Besides taking the standard standover measurement, the LBS guys took another measurement with me kneeling to get my femur-to-tibia ratio. Turns out my femurs are way longer than my tibia. Who knew? I think shoe size went into consideration too. My knees are definitely happier now than when I had 165m cranks. Just so you know my current bike's geometry is way different than the bike I had with the 165m cranks on them, so that may make a difference too.

[OakLeaf]

Good point. Short femurs here.

[madscot13]

how can you tell with the ratio of femur: tibia which crank you need? I've never heard about that and would like to hear more