Originally Posted by
Jiggle
I don't understand. 9-11 speed Shimano cranks are interchangeable and dimensionally identical where it counts. You have your pick.
Not all 10sp cranks are advertised as 9sp compatible (I bought an FSA crank BTW). A 10sp crank can cause rubbing noises if you run it with a wider 9sp chain on it. I'd be surprised if an 11sp crank worked well on a 9sp group.