Originally Posted by
Drew Eckhardt
With my FSA carbon pro compact "9 and 10 speed compatible" crankset and 9 speed chain the chain rubbed on the big ring when using the small ring with the 3-4 smallest cogs thus producing no usable overlap between rings.
I measured the spacing, found it even tighter than Campagnolo 10 speed spacing, and shimmed the small ring inward to make all the gears usable.
That's not surprising as FSA has had crank geometry problems in the past. My LBS replaced a bunch of FSA cranks with Shimano's a few of years ago because of shifting and interference problems like you describe.