Originally Posted by
cyccommute
I'm going to disagree to a certain extent. While the FR-4 can be made to work by removing the lock nut, the
FR-1.2 is thinner and I find that it works better on this kind of freewheel.
I think you might be thinking of a different combination of tools & freewheels. The FR-1.2 has 12 splines. This freewheel has 20 splines, and they're narrower.