Hard to say without photos, but I think this plastic bushing with the metal sleeve should (or whatever this is called in english) over the corrugated/striated(?) middle of handlebar belongs exactly there to fit to the diameter of the handle bar when the allen key is being tightened. There are several systems on the market so I do not know which exact one you have –
__________________
>^..^<*)))>{ All generalizations are wrong.
|