Scroll down the page. I'll keep looking for a pic of measuring a threaded or quill stem but this should get you started.
http://www.nashbar.com/tech/sizebike.cfm
I'm back. Finding of picture of that may be hopeless, but essentially stem length is measured from the center of the headset (the bolt on a quill stem) to the center of the bars and this can obviously vary from stem to stem.
Last edited by SadieKate; 08-02-2007 at 08:15 PM.
Frends know gud humors when dey is hear it. ~ Da Crockydiles of ZZE.