My Wife and I both have Giant OCR1 bikes. I'm 6' riding a large frame, my Wife 5'7" riding a small (men's) frame. Both cranksets are 175mm. We're both in our early 60's and I'm pretty comfortable with the length, but I think my Wife would be more comfortable with shorter crank arms. What are my options in comparable quality in terms of finding 165mm or do I wind up buying something more exotic (read "more expensive")?
I know there is varied opinion regarding crank length and much boils down to personal likes/dislikes, but it seems on the average that the shorter your are the somewhat shorter the crank arm should be.
I'm sure your LBS can find something similar, although it might not be on sale.
If there is a shop in your area who offers a professional fit service (like FitKit, similar offerings from Specialized, etc) it is money well spent, and generalyl includes a crank length reccomendation.
I personally think 165 is very short for someone 5'7", unless she has quite short legs and likes to spin at high rpms... but everyone is different.
Trek 1000, two mtbs and working on a fixie for commuting.
I personally don't feel more or less comfort in the 5mm difference of crank lengths on my two bikes and others have said the same - though I do feel the physical length difference, but if she feels uncomfortable (not you *feel* she is uncomfortable) then I say go for it.
I will add that most people will say, concerning bike size tweaking, to not do too drastic of a change at once so maybe try a 170mm? There also is 172.5 out there, which probably means there might be 167.5, though that last size is probably more rare.