Originally Posted by
Retro Grouch
That's me too only, in my case, it's my left hip that's the problem. For me the sweet spot seems to be 165 mm cranks. I've got 170 mm cranks on my beater. That works OK, but I can tell the difference. I've tried cranks as short as 148 mm on my recumbent bikes. They're OK too but feel a little "choppy".
On my quest, I tried 160's.
They were just too short and made me feel like I was pedaling a kids tricycle. It was too unnatural.