Originally Posted by
JohnDThompson
Actually, ramps in the pawl ring cause the pawl to rock back and forth in a manner that engages the pawl ring with pedal pressure but over-rides the pawls when freewheeling. The biggest problem I encountered is that it can take a while for the pawls to engage, particularly in cold weather when several complete rotations of the crank may occur before they engage!
Sheldon Brown's SW page describes a modification to the SW pawl ring to give it sprung pawls:
I have an SW with this modification and it does work -- for a while. The problem is that the pawl rocks back and forth on the flat spring and eventually wears through it, requiring replacement of the spring.
Sheldon and I talked about the SW... I liked his comment that SW stood for "seldom works" and the amount of extra work it takes to make them functional really isn't worth it when you can run an AW which stands for "always works".
Even latter day AW hubs of British origin, with their less than great workmanship, still provide great service although they are nothing like AW hubs from the 40's and late 50's which are noticeably smoother and when you open them up you can see how much nicer the machining was when the tooling was fresh.