Originally Posted by roadfix
Of course, but you wouldn't be able to spin on a true lockring.
EXACTLY! You can put a fixed cog on a freewheel thread, just like you said. And this leads us to why there are fixed/free hubs made and not just fixed/fixed hubs. If people still don't get it, someone just answer this and I will enlighten...
By putting a fixed cog on the freewheel side of a fixed/free hub & without a lockring as you stated, is the hub now functioning as "fixed" or "free"?