fixedgeargirl notices "One thing no-one has brought up is short cranks."

my first road bike got customised with 165 cm cranks.

my road bike now has 170 cm.

I never had both bikes at the same time I have not compared the two. According to my shop and builder with 170 I get more power on flats and downhill, with 165 the cranks turn over quicker, may be easier spinning up hill.

What is odd is on my old bike, a Trek 420 when I switched to 165 cm I felt an imediate sense of "Aww, not it fits!". But I did not even notice that I had 170 cm cranks now till Adventure girl pointed it out to me on a ride. She's about my height, I'm 5'1" and she has 165 cm. But on this bike 170's's felt "right" to me.

Would I be faster uphill (or at least GET uphill) on 165's? Probably.

Would it fit me less well on this frame? Probably.

It's part of what makes this sport so fascinating, eh?

PS: Happy Birthday Spazzdog