Quote Originally Posted by sundial View Post
Oak, I believe I have 172.5 mm crank arms. I asked my ortho about this some time ago and he seemed ok with it (he's a cyclist as well). The thing is when I spin at a high rpm my R knee is so stiff right off the bike and I walk almost stiff legged for the next hour or so. (Remember Festus from Gunsmoke? ) I didn't have to do this at a cadence of 70-80. I did my first Spinerval of the season and when I finished I was at my dumb knee. I felt great otherwise. I found out I can spin with platform pedals.
Did the ortho have you bring your bike into his office?

Did he put you up in a trainer stand?

Did you spend several minutes spinning before he checked your fit?

Did he check your knee mechanics at several pedal positions?

Did he evaluate your cleat position?