Originally Posted by
Ex Pres
Well dddd & wes, I guess I just haven't paid any attention to modern freewheels - didn't know they had lockrings these days.
That's why I post - to learn things.
See Sheldons explanation of modern lockring freewheels ;
http://sheldonbrown.com/mega7/
Bottom line is that hyperglide cogs need splines (not threads) for alignment but you cannot do a splined cog smaller than 13t unless a separate lockring is used.