Originally Posted by
Chombi
There should be enough gap on the ends of most FD clamps to allow for any slight ST undersizing as you can also use some shimming materials to make up for any gaps.
It's when your seat tube is slightly oversized when you have to worry about, as some FD clamp bodies are quite thick and can put dents on your seat tube if you try to force it on.......
I have four French bikes with 28 mm seat tubes and using 28.6 mm FD's has never been a problem. Just tighten the clamp enough to prevent slippage, but no more than that.
I believe that the Simplex used on Peugeots is identical to the one used on low end Raleighs.
