Originally Posted by FarHorizon
Hi LóFarkas!
+1 for thanking DannoXYZ on his excellent info.
I agree with you on your assessment of relative merits as well but your exception is a HUGE one! Height adjustment is a MAJOR factor in fit, and threadless (unfortunately) is woefully lacking. This sole shortcoming could be easily remedied if manufacturers would begin making stems (and ONLY for those who need them) that allowed both vertical and reach adjustments (beyond the "swinging neck" design offered by all adjustable stem makers). Such stems would, undoubtedly, be less rigid than "standard" threadless stems, but for those who really need height adjustments, they'd be a Godsend.
I don't diss riders who use older quill stems despite the flex. Some riders just like the looks and some need that height adjustment!
I will agree that many current bikes with threadless headsets have very little room for vertical adjustment of the bars. Blame the bike manufactureres. Manufacturers could just leave the steerer tube a bit long and put in some spacers to make this whole thing a non-issue. You can flip a stem back and forth and move spacers up and down in the stack.
Specialized makes a stem with an eccentric shim inside that can be set to +16, +8, -8, and -16 degrees. Couple that with a stack of spacers 20mm high or so and you have a stem that can be adjusted vertically by 2 inches (assuming a 110mm stem). If you leave more spacers in the stack originally, that range can be even greater.
In short, the problem isn't that threadless can't be adjusted vertically. The problem is manufacturers who don't leave any room for vertical adjustment. I think it is comparable to using a quill stem where the minimum insertion point is set so high that it only allows 15mm of vertical adjustment.
God bless!
Wayne J.