In article ,
David L. Johnson wrote:
Very few new bikes have a
spacer on top of the stem, so adjusting the bars upward is only possible
if flipping the stem over raises the position.

Or if you use a steer tube extender. Which works fine and costs
little but is admittedly hideous. But it's nicer than a quill stem in
the sense that you can add rise to any threadless stem, a lot cheaper
and easier than you can find a replacement quill stem with more rise.
If what you want is proper fit, it works fine.

In the case of someone doing a fresh conversion to threadless however,
this really isn't an issue - just buy the right fork.

--Paul