Originally Posted by
Blue Motobecane
I replaced the compression plug and the new one tightened just fine, but I found I couldn't get the headset to sit snugly even after applying too much torque to the preload bolt. It also seemed like the problem was partially that the handlebar stem no longer hit the top spacers at the right angle.
Specialized stems use a special insert that can be rotated / inverted to change the stem angle. This system causes the top of the stem to not be completely flat. You should therefore use one of Specialized's top caps on top of this stem because they are designed to sit at the right angle, and you can rotate them to make them fit better on different angles. One more thing about those stems is that you cannot put a spacer above the stem, because it will also not contact the top of the stem properly. Moving these stems up or down should be done purely by changing the stem's angle using the insert. If you want to go much lower, then you need to cut the steerer column so that the stem is always at the very top.